INCREASES THE DIAMETER OF EACH EXISTING HAIR STRAND HOW IT WORKS: Diaboost™ is a leave-on treatment that can be used with the Nioxin 3-part systems for thicker, denser-looking hair. With HTX, Diaboostª is a fusion of Niacinamide, Panthenol and Caffeine, and is proven to: 1. Boost your existing hair diameter instantly. 2. Penetrate hair and make it manageable and full. 3. Thicken existing hair at the roots. IT IS AS IF YOU HAVE UP TO 11,000 MORE HAIR STRANDS!