Protective Shield is a leave-in spray from Joico's Defy Damage line, applied as the last step before any heat styling. Its full retail name — Protective Shield to Guard Against Thermal & UV Damage — reflects its role: a light mist of silicones, arginine, and moringa seed oil meant to sit on hair through blow-drying, flat-ironing, or curling rather than being rinsed out.

• Applied to clean, damp hair and combed through before blow-drying or styling
• Contains Arginine, which bonds to hair's structure to help reinforce strands
• Contains Moringa Oleifera Seed Oil for antioxidants and vitamins A and E
• Formulated with a blend of silicones for smoothing and glide during heat styling
• Can be used daily, on most hair types

Because it's left in rather than rinsed, its role is different from the shampoo and conditioner in the same line — it's the layer that stays on hair while heat tools are actually in use, rather than a wash-day step.

Water/Aqua/Eau, Dimethicone, Cetearyl Alcohol, Behentrimonium Chloride, Cinnamidopropyltrimonium Chloride, C12-15 Alkyl Benzoate, Myristyl Alcohol, Cocos Nucifera (Coconut) Oil, Moringa Oleifera Seed Oil, Arginine, Avena Sativa (Oat) Peptide, Phosphatidylcholine, Rosa Canina Fruit Oil, Tocopherol, Laurdimonium Hydroxypropyl Hydrolyzed Keratin, Arginine HCl, Silicone Quaternium-16, Aminopropyl Dimethicone, Disodium EDTA, Trimethylsiloxyamodimethicone, Dipropylene Glycol, Undeceth-11, Steartrimonium Chloride, C10-40 Isoalkylamidopropylethyldimonium Ethosulfate, PEG-4 Laurate, Butyloctanol, C11-15 Pareth-7, Citric Acid, Undeceth-5, C12-16 Pareth-9, Glycerin, Trideceth-12, PEG-6 Methyl Ether Dimethicone, Aminomethyl Propanol, Isopropyl Alcohol, Phenoxyethanol, Iodopropynyl Butylcarbamate, Citronellol, Alpha-Isomethyl Ionone, Limonene, Fragrance/Parfum