System Professional Conditioners (20)

Regenerate, protect, and smooth damaged hair with the powerful System Professional Lipid Booster—a breakthrough treatment formulated to deeply restore the hair’s inner structure and protect against daily wear and tear. Whether your hair is bleached, highlighted, or severely damaged, this advanced formula rebuilds broken bonds and strengthens hair from the inside out. Why We Love It 💪 Up to 9x more protection from daily damage* 🛡 Creates a protective barrier to reduce breakage ✨ Instantly improves softness and manageability 🔬 Enriched with LipidCode™ Complex, PLEX, and Squalane ✔ Ideal for damaged, bleached, or colour-treated hair *vs low-conditioning shampoo What It Does This luxurious weekly strengthening treatment penetrates deep into the hair fibre to rebuild internal lipids, repair weakened bonds, and fortify hair from root to tip. With continued use, it enhances the results of any Lipid Booster+ salon service, prolonging protection while giving your hair a smooth, revitalised texture and salon-level care at home. How to Use Apply to clean, towel-dried hair, focusing on the mid-lengths and ends. Leave on for 5–10 minutes. Rinse thoroughly. ✨ Use once a week to maintain strong, silky, and protected hair. Key Ingredients LipidCode™ Complex – Rebuilds hair's natural lipid layer for lasting strength. PLEX Technology – Creates new bonds within the hair fibre to repair damage. Squalane – Provides lightweight moisture and boosts smoothness. Full Ingredients List Aqua/Water/Eau, Propylene Glycol, Behentrimonium Chloride, Amodimethicone, Quaternium-80, Cetrimonium Chloride, Isopropyl Alcohol, Panthenol, Malic Acid, Methylparaben, Parfum/Fragrance, Trideceth-12, Squalane, Caffeine, Histidine, Sodium Hydroxide, Disodium EDTA, Phenoxyethanol, Oleic Acid, Glyceryl Oleate, Citric Acid, Benzyl Salicylate, Hexyl Cinnamal, Limonene, Geraniol, Linalool, Lecithin, Ascorbyl Palmitate, Tocopherol, Hydrogenated Palm Glycerides Citrate.

Hydrates Smoothes  Lightweight  System Professional Hydrate Shampoo & Conditioner Duo (2 x 1000ml) 1 x System Professional Hydrate Shampoo (1000ml) - a gentle cleanser for dry hair which restores the hair’s natural moisture balance with its lightweight formulation. It leaves the hair soft, smooth and supple with excellent combability. In order to derive maximum benefit, follow with SP Hydrate Conditioner. 1 x System Professional Hydrate Conditioner (1000ml) - a quenching cream conditioner which restores moisture balance in normal to dry hair. Perfect for detangling long hair, it provides softness, hydration and combability without weighing hair down. In order to derive maximum benefit, use together with SP Hydrate Shampoo. How to use: Shampoo - apply 1 pump of shampoo into damp hair and distribute evenly. Work into a lather and massage gently. Rinse thoroughly. Conditioner - after shampooing with System Professional Hydrate Shampoo, apply 1 - 2 pumps of the conditioner onto towel-dried hair. Comb through and leave for 30 seconds. Emulsify and rinse thoroughly. Apply finishing product and style as usual. Ingredients Hydrate Shampoo:  Aqua/Water/Eau, Sodium Laureth Sulfate, Sodium Lauryl Sulfate, Sodium Chloride, Panthenol, Cocamidopropyl BetaineParfum/Fragrance, Sodium Benzoate, Citric Acid, Glycerin, Salicylic Acid, Hydroxypropyl Methylcellulose, Tetrasodium EDTA, Caffeine, Methylparaben, Sodium Hydroxide, Benzyl Salicylate, Histidine, Hexyl Cinnamal, Hexylene Glycol, Limonene, Fructose, Glucose, Oleic Acid, Glyceryl Oleate, Dextrin, Sucrose, Urea, Yellow 5 (CI 19140), Alanine, Aspartic Acid, Glutamic Acid, Hexyl Nicotinate, Red 33 (CI 17200), BHT, Sodium Citrate, Sodium Xylenesulfonate, Lecithin, Ascorbyl Palmitate, Tocopherol, Hydrogenated Palm Glycerides Citrate. Ingredients Hydrate Conditioner: Aqua/WaterIngredient Hydrate Shampoo: /Eau, Cetyl Alcohol, Stearamidopropyl Dimethylamine, Glycerin, Oleic Acid, Stearyl Alcohol, Quaternium-18, Parfum/Fragrance, Panthenol, Benzyl Alcohol, Phenoxyethanol, Cetearyl Alcohol, Hydroxypropyl Guar, Bis-Aminopropyl Dimethicone, Glyceryl Stearate SE, Oleyl Alcohol, Methylparaben, Propylparaben, Polysorbate 60, Glyceryl Oleate, Caffeine, EDTA, Citric Acid, Benzyl Salicylate, Histidine, Hexylene Glycol, Hexyl Cinnamal, Limonene, Fructose, Glucose, Dextrin, Sucrose, Urea, Yellow 5 (CI 19140), Alanine, Aspartic Acid, Glutamic Acid, Hexyl Nicotinate, Red 33 (CI 17200), Lecithin, Ascorbyl Palmitate, Tocopherol, Hydrogenated Palm Glycerides Citrate, BHT.

Hair feeling dry, rough or difficult to manage? System Professional LuxeOil Keratin Conditioning Cream is a fast-acting, lightweight conditioner that softens, smooths and protects hair’s keratin structure in just 30 seconds — without heaviness. ✔ Instant softness in 30 seconds✔ Helps protect keratin and strengthen the hair fibre✔ Smooths and detangles for easy combing✔ Adds shine without weighing hair down✔ Suitable for daily use on all hair types Best For • Dry or dull hair• Hair lacking softness and shine• Coloured or heat-styled hair• Hair that tangles easily• Anyone wanting lightweight daily nourishment For Best Results Use after LuxeOil Keratin Protect Shampoo, then finish with LuxeOil Reconstructive Elixir for enhanced shine, smoothness and protection. ✨ System Professional LuxeOil Keratin Conditioning Cream Smooth, strengthen and nourish your hair with System Professional LuxeOil Keratin Conditioning Cream, a luxurious daily conditioner designed to deliver silky-soft results in just 30 seconds. This lightweight yet deeply nourishing formula helps protect the hair’s keratin structure while improving softness, manageability and shine. Hair feels instantly smoother, easier to comb and beautifully conditioned — without heaviness or residue. Enriched with a blend of Argan, Jojoba and Almond Oils, the conditioning cream helps defend against styling stress, restore hydration and enhance the hair’s natural radiance for a smooth, salon-quality finish every day. Why We Love It ✔ Visible results in just 30 seconds✔ Helps protect keratin and hair fibres✔ Smooths and softens for effortless combing✔ Lightweight formula suitable for daily use✔ Leaves hair shiny, soft and manageable How to Use After shampooing, apply to towel-dried hair Focus on lengths and ends Leave for 30 seconds Rinse thoroughly For enhanced results, finish with LuxeOil Reconstructive Elixir. Key Ingredients Argan Oil – nourishes and enhances shine Jojoba Oil – strengthens and helps protect the hair fibre Almond Oil – smooths hair and combats dryness Technology Highlight – FibraNourish Complex An intelligent blend of premium oils designed to deliver long-lasting moisture and keratin protection, leaving hair softer, stronger and more resilient.

Suitable for: Dehydrated, dry, and static-prone hair Restore softness and hydration with System Professional Hydrate Conditioner 200ml, a lightweight yet deeply nourishing conditioner formulated to quench normal, dry, and damaged hair. Enriched with the Active Moisture Complex and Pro Vitamin B5, this hydrating conditioner penetrates deep into the hair fibre to restore lost moisture, replenish essential nutrients, and improve flexibility. Hair is left feeling silky, smooth, and manageable, with long-lasting softness and shine. Key Benefits ✔️ Intense hydration – replenishes lost moisture deep within the hair shaft. ✔️ Softens & smooths – reduces static, tames frizz, and adds shine. ✔️ Strengthens & protects – fortifies hair from the inside out for improved resilience. ✔️ Lightweight formula – nourishes without weighing hair down. Perfect For Normal hair that feels dry or dull. Dehydrated hair needing lasting hydration. Damaged hair that requires softness and flexibility. With regular use, System Professional Hydrate Conditioner helps maintain optimal moisture levels, leaving hair looking healthier, smoother, and full of vitality.

System Professional Color Save Conditioner is a deeply hydrating, fast-absorbing formula designed to protect, soften, and enhance the vibrancy of colour-treated hair. Perfect for post-salon care, this professional-grade conditioner works to detangle, smooth flyaways, and prolong colour brilliance. Powered by Fibrachrome Complex and a built-in UV filter, it shields hair from external stressors that cause colour fading, while nourishing each strand from root to tip. The result? Soft, shiny, salon-fresh hair with noticeably fewer split ends. Key Benefits 🎨 Prolongs colour vibrancy and radiance☀️ UV filter protects against sun-induced fading✨ Reduces split ends and frizz for a sleeker finish💧 Detangles and softens without weighing hair down🧴 Ideal for daily use on colour-treated and highlighted hair💆♀️ Fast-acting – results in just 30 seconds How to Use After shampooing with System Professional Color Save Shampoo, apply conditioner to towel-dried hair. Comb through to distribute evenly. Leave in for 30 seconds. Emulsify and rinse thoroughly. Follow with styling products or treatments as needed. Perfect For Coloured and highlighted hair Maintaining salon colour Softening and detangling Smoothing flyaways and split ends All hair types, especially dry or treated hair Technology 💡 Fibrachrome Complex – helps maintain colour tone and depth🛡️ UV Filter – shields hair from sun exposure and damage Size: 1000ml / 1 Litre Packaging: May vary depending on batch.

System Professional Hydrate Conditioner 1ltr Suitable for dehydrated static prone  is a quenching cream conditioner which restores moisture balance in normal to dry hair. Perfect for detangling long hair, it provides softness, hydration and combability without weighing hair down. In order to derive maximum benefit, use together with SP Hydrate Shampoo. Directions of use: After shampooing with System Professional Hydrate Shampoo, apply 1 - 2 pumps of the conditioner onto towel-dried hair. Comb through and leave for 30 seconds. Emulsify and rinse thoroughly. Apply finishing product and style as usual.

Suitable For: Hair damaged by sun and chlorine Replenish, repair, and restore your hair after sun, salt, and pool exposure with System Professional Solar Conditioner. This nourishing formula is designed to rewind the effects of summer stress on your hair—hydrating strands that have been stripped of moisture and softness from prolonged sunbathing or swimming in chlorinated or salty water. Why We Love Solar Conditioner ☀️ Repairs Sun-Damaged Hair – Helps reverse visible signs of sun stress🌊 Replenishes Moisture – Restores hydration lost through chlorine and salt✨ Improves Combability – Detangles effortlessly, leaving hair soft and manageable💧 Smooth, Silky Finish – Boosts natural shine and silkiness without weighing hair down🏖️ Ideal for Summer or Sporty Lifestyles – A must-have for swimmers and sun-lovers How It Works Powered by the HelioRestore Complex, this targeted treatment goes deep into the hair structure to repair sun-induced damage, replenish hydration, and smooth the cuticle. Whether you’ve spent the day at the beach or in the pool, this conditioner brings your hair back to life—soft, sleek, and radiantly healthy. How to Use After shampooing (preferably with System Professional Solar Shampoo), apply evenly to towel-dried hair. Comb through to distribute. Leave in for 30 seconds to 2 minutes. Rinse thoroughly. Perfect For: ✔ Sun-stressed, dry, or brittle hair✔ Hair exposed to chlorine or saltwater✔ Post-sport or summer haircare routine✔ Boosting shine, smoothness, and softness Pro Tip: Mix with System Professional Solar Sun Oil for an ultra-luxurious conditioning treatment that boosts softness and adds extra protection against frizz and flyaways. Size: Available in standard 200ml tube

Revitalise dry, damaged, or natural hair with System Professional Hydrate Quenching Mist H5. This lightweight, leave-in conditioning spray delivers instant hydration, enhances manageability, and boosts the effectiveness of masks and treatments. Infused with LipidCode™ technology and key ingredients like glycerin, panthenol, glucose, and fructose, it restores moisture balance, leaving hair soft, silky, and resilient. 💧 Key Benefits of System Professional Hydrate Quenching Mist Deep hydration for dry and damaged hair Improves manageability and detangling Enhances the performance of masks and emulsions Strengthens hair against breakage Lightweight, non-greasy formula How to Use: Spray evenly onto towel-dried hair. Comb through to distribute. Do not rinse. Style as desired. Ingredients: Aqua (Water), Alcohol Denat., Cetyl Alcohol, Panthenol, Glycerin, Cetrimonium Chloride, Parfum (Fragrance), Polyquaternium-10, Isopropyl Alcohol, Ethylhexyl Methoxycinnamate, Hexylene Glycol, Benzyl Salicylate, Hexyl Cinnamal, Glucose, Fructose, Limonene, Geraniol, Urea, Sucrose, Dextrin, Hexyl Nicotinate, Glutamic Acid, Aspartic Acid, Alanine. 

  Professional-size conditioner for dry, damaged and chemically treated hair For hair that needs ongoing repair, System Professional Repair Conditioner 1000ml delivers salon-quality strengthening and softness in a generous professional size. Ideal for frequent use, long hair, or households sharing a professional haircare routine, this conditioner helps restore over-processed hair while improving manageability and shine. Used by professionals, the rich yet balanced formula works to repair weakened hair fibres, smooth the cuticle and reduce the appearance of split ends and frizz — without leaving hair heavy or coated. Why professionals choose the 1 litre size Helps repair and strengthen damaged hair Improves manageability and reduces breakage Smooths the cuticle for softer, shinier hair Protects hair from future damage Excellent value for regular use or professional routines Ideal for dry, damaged, bleached or chemically treated hair How it works Formulated with Hydrolysed Keratin, this conditioner helps reinforce the internal structure of weakened hair, while Wheat Germ Oil nourishes and softens dry, over-processed lengths. The result is hair that feels smoother, stronger and more resilient with continued use. When used consistently as part of a professional repair routine, hair becomes easier to style, less prone to breakage and visibly healthier. How to use After shampooing, apply to towel-dried hair.Massage through mid-lengths and ends, leave for 30 seconds, then rinse thoroughly. For best results, pair with System Professional Repair Shampoo and a weekly repair or bond-building treatment. Suitable for Dry hair Damaged hair Bleached or chemically treated hair Weak or breakage-prone hair Regular or professional use Key ingredients Hydrolysed Keratin, Wheat Germ Oil Ingredients list Aqua, Cetyl Alcohol, Stearamidopropyl Dimethylamine, Stearyl Alcohol, Quaternium-18, Phenoxyethanol, Benzyl Alcohol, Cetearyl Alcohol, Hydroxypropyl Guar, Parfum, Bis-Aminopropyl Dimethicone, Glyceryl Stearate, Oleyl Alcohol, Methylparaben, Propylparaben. Professional tip The 1000ml size is ideal if you’re repairing hair over time. Consistent use is key when improving damaged hair — pairing this conditioner with a repair shampoo and treatment delivers the best long-term results.  

Say goodbye to colour fade and hello to radiant, silky hair with System Professional Color Save Conditioner. This lightweight, nourishing formula is specially designed for colour-treated hair, helping to prolong vibrancy, smooth the cuticle, and add mirror-like shine. Formulated with the Fibrachrome Complex and an effective UV filter, it works to detangle and protect the hair fibre while locking in colour pigments. Your hair is left feeling hydrated, soft, and manageable, with long-lasting colour brilliance. Key Benefits of System Professional Color Save Conditioner 💧 Lightweight formula that hydrates and detangles 🎨 Preserves colour vibrancy and reduces fading 🌞 UV filter helps defend hair against environmental damage ✨ Enhances shine and smoothness from root to tip 💆♀️ Delivers salon-quality softness at home ✔️ Only 30-second development time How to Use Shampoo hair with your chosen System Professional Shampoo. Apply a small amount of conditioner to towel-dried hair. Comb through to distribute evenly. Leave on for 30 seconds, then emulsify and rinse thoroughly. Who is it for? 🎯 Ideal for coloured, dyed, or highlighted hair 🌈 Anyone looking to maintain colour brightness between salon visits ✨ Perfect for hair that needs shine, detangling, and softness Why You'll Love It 🧬 Powered by Fibrachrome Complex for colour retention 🌞 Contains a UV filter for added protection 💆♀️ Leaves hair touchably soft, sleek, and shiny 🌱 Suitable for regular use without weighing down hair Size: 200ml Pair It With: 🧴 System Professional Color Save Shampoo 💆♀️ System Professional Color Save Mask

Suitable for- Dry, Course, Unruly Hair Effortlessly detangle unruly locks with the System Professional Smoothen Conditioner; a calming formula developed to hydrate, control and tame hair. Powered by the brand's EnergyCode™ Complex, the weightless conditioner penetrates deep into rebellious, coarse and curly hair to soften and smoothen, whilst fighting frizz to reveal super sleek, salon-worthy results. Hair is manageable and easier to style with enhanced shine.

Smooth. Strengthen. Shine. Transform your hair care routine with the System Professional LuxeOil Keratin Conditioning Cream (1L)—a daily conditioner designed to nourish and protect all hair types. This luxurious formula delivers instant softness, strengthens hair fibres, and enhances shine without weighing your hair down. Key Benefits: Instant Softness: Leaves hair touchably soft and manageable in just 30 seconds. Keratin Protection: Fortifies the hair's natural keratin structure, reducing breakage and split ends. Daily Nourishment: Provides essential hydration and nutrients for healthy-looking hair. Enhanced Shine: Adds a radiant finish, leaving hair glossy and vibrant. Lightweight Formula: Suitable for daily use without causing build-up. How to Use: After shampooing, apply 1–2 pumps of the conditioner onto towel-dried hair. Distribute evenly through the lengths and ends. Leave for 30 seconds. Rinse thoroughly. For best results, use with System Professional LuxeOil Keratin Protect Shampoo. Key Ingredients: Argan Oil: Known as "liquid gold," it enhances elasticity and provides deep nourishment. Jojoba Oil: Rich in vitamins and minerals, it moisturises and strengthens hair. Almond Oil: Adds lustre and smoothness, combating dryness and frizz. Ingredients List: Aqua (Water), Stearyl Alcohol, Cetyl Alcohol, Stearamidopropyl Dimethylamine, Oleic Acid, Phenoxyethanol, Benzyl Alcohol, Parfum (Fragrance), Bis-Aminopropyl Dimethicone, Dicetyldimonium Chloride, Glutamic Acid, Methylparaben, Propylparaben, Glyceryl Oleate, Caffeine, EDTA, Propylene Glycol, Histidine, Sodium Chloride, Amyl Cinnamal, Hexyl Cinnamal, Linalool, Argania Spinosa Kernel Oil, Prunus Amygdalus Dulcis (Sweet Almond) Oil, Simmondsia Chinensis (Jojoba) Seed Oil, Hydrolyzed Keratin, CI 19140, CI 17200, BHT, Lecithin, Ascorbyl Palmitate, Tocopherol, Sorbic Acid, Hydrogenated Palm Glycerides Citrate.

Quench your hair’s thirst with the System Professional Hydrate Mask – the ultimate weekly hydration boost for dehydrated, static-prone, and rough hair. This luxurious mask is enriched with glycerin and a Hydro-Deposit™ formula, specially developed to restore moisture balance, leaving hair silky, smooth, and deeply nourished. Perfect for fine to normal hair types, this intensely moisturising treatment improves manageability, reduces flyaways, and delivers a lasting, healthy shine. Key Benefits of System Professional Hydrate Mask 💧 Intensely hydrates dry, rough, or static-prone hair 🧪 Powered by Hydro-Deposit™ Technology for long-lasting moisture 🧴 Enriched with Glycerin to smooth and soften 🧖♀️ Makes hair more manageable and easier to style 💆♀️ Salon-quality treatment for home use 🌟 Leaves hair refreshed, shiny, and luxuriously soft How to Use Shampoo your hair and gently towel dry. Apply a coin-sized amount of the Hydrate Mask to lengths and ends. Twist and twirl the hair to ensure even distribution. Leave in for 5–10 minutes. Rinse thoroughly and style as usual. Use weekly, or as needed for intensive hydration. Who is it for? 🌬️ Dry, dehydrated hair in need of moisture ⚡ Static-prone or frizzy hair 💁♀️ Fine to normal hair types 🌿 Anyone looking for softness, shine, and hydration without heaviness Ingredients Aqua/Water/Eau, Stearyl Alcohol, Cetyl Alcohol, Glycerin, Stearamidopropyl Dimethylamine, Oleic Acid, Parfum/Fragrance, Panthenol, Dimethicone, Benzyl Alcohol, Phenoxyethanol, Dicetyldimonium Chloride, Glutamic Acid, Bis-Aminopropyl Dimethicone, Glyceryl Oleate, Methylparaben, Propylparaben, Propylene Glycol, Caffeine, EDTA, Benzyl Salicylate, Histidine, Hexylene Glycol, Hexyl Cinnamal, Sodium Chloride, Limonene, Fructose, Glucose, Citric Acid, Dextrin, Sucrose, Urea, Yellow 5 (CI 19140), Alanine, Aspartic Acid, Hexyl Nicotinate, Red 33 (CI 17200), Lecithin, Ascorbyl Palmitate, Tocopherol, Hydrogenated Palm Glycerides Citrate, BHT. Size: 400ml

Professional conditioner for dry, damaged and chemically treated hair If your hair feels weak, rough or over-processed, it needs more than moisture — it needs targeted repair. System Professional Repair Conditioner is a salon-grade formula designed to strengthen and restore damaged hair while improving manageability and softness from the very first use. Used by professionals, this rich yet lightweight conditioner helps repair weakened hair fibres, smooth the cuticle and reduce the appearance of split ends and frizz — without weighing hair down. Why professionals recommend it Helps repair and strengthen damaged hair Improves manageability and reduces breakage Smooths the cuticle for softer, shinier hair Protects hair from future damage Ideal for dry, damaged, bleached or chemically treated hair How it works The conditioning formula is enriched with Hydrolysed Keratin to help reinforce weakened hair structure, while Wheat Germ Oil nourishes and softens dry, over-processed hair. Together, they help restore resilience, improve elasticity and leave hair feeling healthier over time. With continued use as part of a professional repair routine, hair feels stronger, smoother and more manageable. How to use After shampooing, apply to towel-dried hair. Massage through lengths and ends, leave for 30 seconds, then rinse thoroughly. For best results, use alongside System Professional Repair Shampoo and a weekly repair mask. Suitable for Dry hair Damaged hair Bleached or chemically treated hair Weak or breakage-prone hair Key ingredients Hydrolysed Keratin, Wheat Germ Oil Ingredients list Aqua, Cetyl Alcohol, Stearamidopropyl Dimethylamine, Stearyl Alcohol, Quaternium-18, Phenoxyethanol, Benzyl Alcohol, Cetearyl Alcohol, Hydroxypropyl Guar, Parfum, Bis-Aminopropyl Dimethicone, Glyceryl Stearate, Oleyl Alcohol, Methylparaben, Propylparaben. Professional tip For damaged hair, conditioners work best when paired with a bond-repair or strengthening treatment. Use regularly to maintain softness while improving hair strength over time.

System Professional LuxeBlond Hair Mask is a luxurious treatment designed specifically for blonde hair, whether natural, highlighted, or bleached. This mask deeply restores hair from the core while instantly neutralising brassy and yellow undertones, resulting in cool, luminous blonde tones. Formulated with the innovative LipidCode™ Complex and violet pigments, it offers up to 84% stronger hair against breakage and up to 83% smoother hair after just one application  Key Benefits of LuxeBlonde Hair Mask 400ml Neutralises yellow and brassy tones for a cooler blonde appearance. Deeply restores and strengthens hair from within. Enhances smoothness and shine, leaving hair soft and manageable. Protects against environmental damage and replenishes essential moisture. Suitable for all blonde hair types, including natural, highlighted, and bleached hair. How to Use Apply the mask evenly onto damp hair. Leave in for 5 minutes. Rinse thoroughly. Use weekly for optimal results. Ingredients Aqua/Water/Eau, Stearyl Alcohol, Bis-Aminopropyl Dimethicone, Behentrimonium Methosulfate, Cetyl Alcohol, Parfum/Fragrance, Phenoxyethanol, Dicetyldimonium Chloride, Isopropyl Alcohol, Methylparaben, Propylparaben, Disodium EDTA, Glyceryl Oleate, Propylene Glycol, Caffeine, Carthamus Tinctorius (Safflower) Seed Oil, Oleic Acid, Acid Violet 43, Benzyl Salicylate, Alpha-Isomethyl Ionone, Hexyl Cinnamal, Limonene, Histidine, Lecithin, Ascorbyl Palmitate, Tocopherol, Hydrogenated Palm Glycerides Citrate, Sodium Hydroxide.