For over 40 years, Kryptonite has been the leader in action sports security, and their Evolution Series 4 Disc Lock shows exactly why they'll continue to lead the industry. Its 14mm hardened MAX-Performance steel shackle resists cutting and leverage attacks, while the double deadbolt locking mechanism has extensive holding power. It's equipped with a high-security, disc-style cylinder that's reinforced for anti-drill and anti-pull protection, and the sliding dust cover protects and extends cylinder life from debris.