WHAT IT IS Interchangeable brush heads stay securely on the handle while coloring, but are easily removed for cleaning. Includes, 1-Ultra Feather Bristle 1-Firm Bristle. WHAT IT DOES Quickly and easily change between feather and firm bristles. WHAT ELSE YOU NEED TO KNOW The Ambassador Collection was conceptualized with Colotrak's team of brand ambassadors and salon experts to be the first collection truly for stylists by stylists.