Kryptonite Evolution Standard Lock is a robust U-lock made of 14 mm thick super-strong steel. It's the safest option for safeguarding your bike against thieves, providing a high level of burglar resistance. You can easily transport the U-lock using the included holder, or alternatively, carry it in a backpack or bike bag when needed. The lock's hardened steel arc is highly resistant to breaking or splitting, and the lock seat is also designed to withstand force. When using a U-lock, it's recommended to secure the bike to a sturdy object, looping the lock around the frame and rear wheel if possible. Ultra-strong 14 mm hardened steel shackle resists cutting and prying attempts Three stainless steel keys with one LED key fob for added visibility Double deadbolt protection: Patented design defends against twist attacks Compact design: Smaller crossbar for easier carrying. Pick and drill resistant: High-security disc-style cylinder deters tampering Multiple mounting options: Flexframe-U bra