Click to expand Tap to zoom Wella Koleston Perfect - 10/16 Lightest Blonde Ash Violet by Wella Sold out Please register or login to view prices. SKU 81610364 Koleston Perfect is the first professional hair color brand to feature breakthrough technologies boasting pure, balanced color results with natural depth and shine. Simple 1:1 mixing ratio. Up to 100% grey coverage. Up to 5 levels of lift.