Kryptonite Standard U-lock with FlexFrame bracketThe Kryptonite Standard U-lock with FlexFrame bracket features a high-performance, 13mm thick hardened steel shackle that's specially designed to resist cutting and leverage attacks. Its patent pending hardened double deadbolt is resistant to twisting attacks and there's also a disc-style cylinder lock, which is pick and drill resistant.Convenient and Quiet On The GoKryptonite added anti-rattle bumpers to this lock so to minimize vibration noise when you're riding over cobbled streets or poor road surfaces. Also included, is Kryptonite's Transit FlexFrame-U transportation system, which can be mounted in various points on your bike's frame for convenience. The lock comes complete with 2 tough stainless steel keys.Features:  Sold Secure Bicycle Silver Certified  Easy to transport  13mm hardened performance steel shackle  Double deadbolt design  High security disc-style lock  Includes Transit FlexFrame-U transportation system  Key safe program  Optional ATPO (Anti-Theft Protection Cover)  Dimensions: 10.2cm x 22.9cm  Weight: 1.32kgEuropean Testing Agencies  In Europe, independent testing agencies put locks through their paces to see how secure they really are, or in some cases are not. Kryptonite holds more than 45 approvals at Sold Secure (UK), ART (NL), VdS (DE), N.F. (FRA), Classe SRA (FRA), SSF (Sweden) and VAREFAKTA (Den). These agencies attacked products with every bit of malice the testers could throw at them and they still held up. We hope this brings peace of mind to Kryptonite customers.Buy Kryptonite Accessories from Chain Reaction Cycles, the World's Largest Online Bike Store.