These are the ingredients according to the cult beauty website -
Step 1 Release: Aqua, Isostearamidopropyl Morpholine Lactate, Hydroxypropyltrimonium, Hydrolyzed Wheat Protein, Hydroxycellulose, PEG-40 Hydrogenated Castor Oil, arfum, Trideceth-9 Gluatmix Acid, Arginine, Serine, Proline, Aspartic Acid, Threonine, Valine, Alanine, Glycine, Lycine, Leucine, Phenylalinine, Cysteine, Histidine, Methionine, Tyrocine, Tryptophan, Benzyl Alcohol, Methylchloroisothiazolinone, Methylisothiazolinone, Magnesium Chloride, Magnesium Nitrate. Step 2 Revive: Aqua, Ammonium Laureth Sulphate, Ammonium Lauryl Sulphate, Cocoamide MEA, Glyceryl Oleate, PEG-18 Glyceryl Oleate/Cocoate, Glycol Stearate, Panthenyl Ethyl Ether, Hydroxypropyltrimonium Honey, Parfum, Cocodimonium Hydroxy-Propyl Hydrolysed Wheat Protein, Benzophenone-3, Disodium EDTA, Octyl Methoxycinnamate, Tocopheryl Acetate, Dimethcione Coployl, Citric Acid, Hexylene Glycol, Sodium Chloride, Benzyl Alcohol, Methylchloroisothiazolinone, Methylisothiazonlinone, Magnesium Chloride, Magnesiu, Nitrate, Sodium Hydrozude, CI15985. Step 3 Replenish: Aqua, Cetearyl Alcohol, Cetyl Pyridinium Chloride, PEG/PPG-20/6 Dimethicone, Parfum, Glutamic Acid, Arginime, Serine, Proline, Aspartic Acid, Threonine, Valine, Alanine, Glycine, Lycine, Leucine, Phenylalanine, Cysteine, Histidine, Methionine, Tryptophan, Titanium Dioxide, Phenoxyethanol, Methylparaben, Propylparaben, Ethylparaben, Butylparaben, Isobutylparaben, Benzyl Salicylate, Benzyl Alcohol, Geraniol Cover up your sins
I'd check the bottle if you are sensitive to ingredients as I've often found the ones listed online aren't complete or correct.
What does annoy me is when they say 100ml is 3 months use if you use weekly. If you have long/thick/dry/curly hair 100ml of conditioner might not even do two washes - reality! If 100 ml of conditioner lasts you more than 10 washes, you're not using enough or you don't need conditioner unless your hair is very short/fine/super shiny naturally! I do know people who have shiny hair without any conditioner, but they wouldn't need this kit!