No.5 Strengthening Conditioner (formerly No.5 Bond Maintenance Conditioner)
Key ingredients: Olaplex Bond-Building Technology (patented; appears in the ingredient list as Bis-Aminopropyl Diglycol Dimaleate)
Rinse-out conditioners, masks and bond-care treatments for softer, easier-to-comb hair.

Conditioners coat the hair to make it smoother and easier to detangle, which reduces breakage from combing. Masks are richer, leave-on-for-longer versions. Apply them to the mid-lengths and ends rather than the scalp.
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Key ingredients: Olaplex Bond-Building Technology (patented; appears in the ingredient list as Bis-Aminopropyl Diglycol Dimaleate)
Key ingredients: Hydrolyzed Elastin, Castor Oil, Olive Oil, Glycerin
Key ingredients: Aminexil; Biotin; Arginine
Key ingredients: Collagen Peptides (synthetic Palmitoyl Tripeptide-1 and Palmitoyl Tetrapeptide-7)
Key ingredients: Oats (Avena Sativa kernel flour, kernel oil and bran extract); shea butter