Planet Bike Mountie Mini U Lock with Chain Four-sided trapezoidal ultra-hardened steel links and Mini U-lock defy bolt cutters, saws, chisels, hammers, files and leverage attacks Mini U-Lock has hardened steel shackle and bar with easy to use high-security barrel key w/ hidden pin For medium- to high-risk theft areas Durable weatherproof nylon sleeve protects bicycles finish 100 cm chain