Goldwell Dualsenses Rich Repair 6 Effects Serum An innovative 6-in-1 solution for hair that's in need of some TLC, this Dualsenses Rich Repair 6 Effects Serum from Goldwell is your fast track to super soft, silky hair. Boasting six repairing benefits, this effective serum gives your hair instant shine with an anti-frizz effect, healthy ends and improved elasticity.