Force architecte is dedicated for damaged hair with erosion level 1-2 while Thérapiste is specifically suited for hair with an erosion of 3-4 usually very damaged and over-processed hair.
How do you know your hair's erosion level?
If your hair look dead and feel weak, have split ends, dry hair that appears dull you probably need the Resistance Thérapiste for hair with an erosion level of 3-4. If you are unsure you can always go to your nearest Kérastase salon for an in-depth hair consultation.
A MAJOR SCIENTIFIC DISCOVERY: THE KAPS