The Nimbus Microfine has two states of soft bristles: long-tapered extra fine bristles to reach into those critical areas with the required softness and effectiveness - coupled with shorter, fine support bristles to enhance optimum plaque removal. Microfine toothbrushes use a multi-tufted, soft bristle technology mounted on a comfort-engineered handle. Long tapered and short end rounded extra-fine, flexible bristles clean the hard to reach places; gently and effectively. The Nimbus Microfine has been tested and evaluated by dental professionals. The result is the best brush you or your patients will ever use. The 5 pack comes in assorted colors. Nimbus is a registered trademark of Periscope Enterprises, Inc.