The Kryptonite Evolution Mini-5 U-Lock features a 13mm hardened maximum performance steel shackle and a double deadbolt anti-rotational design to withstand bolt cutters and torsional leverage attacks. Disc style cylinders with center keyway are protected with vinyl coating to resist picks and drills. The keyway has a sliding dust cover to protect the cylinder from dirt and debris when not in use. Includes 3 stainless steel keys with ergonomic design to reduce torque and wont bend or break. One of the keys has LED key fob to increase visibility in the dark. Rated at 7/10 in our security scale, the Evolution Mini-5 is ideal for quick stopping on the college campus or for all-day and night use in major metropolitan areas, as well as for hours on suburban and rural areas. It also includes a patented FlexFrame-U bracket for convenient multi-location U-lock transportation. With these great features and support programs such as key safe, anti-theft protection, and lifetime time, Kryptonite bike locks are the best choice for protecting your valuables.