all three are hair treatment masks to use after shampoo. a bit of difference in their usage though.
1. KMS - is LPP formula, similar to many general hair treatment in the market that repair damaged hair.
2. milk keratin - is also used to repair damaged hair, but this treatment can more specifically apply to damaged and splits ends (via "soak" method - dilute with water to soak hair ends).
3. silky hair enzyme - more specifically use for dry, coarse, frizzy, protein deprived hair. for this treatment, silky effect could be very visible in just one wash !
basically for all three treatment, is used after shampoo (massage on hair 3-5mins). but if u have more specific needs, please select accordingly.
let me know if u have any more questions. hope i helped :)