The FiveFingers Performa was designed to enhance a barefoot feeling. The kangaroo leather upper feels soft against the bare foot, yet is strong and tear resistant. The 7-part Vibram rubber sole offers maximum feel and flexibility without sacrificing slip resistance. The Performa was designed primarily for indoor use during fitness training, CrossFit, and for after sport. The sole is not designed for extended use during outdoor activities like trekking, running, or water sports.