14mm hardened MAX-Performance steel shackle resists cutting and leverage attacks * Higher security disc-style cylinder * Double deadbolt locking for extensive holding power * 3 keys-one lighted with high intensity bulb and replaceable battery * Includes Transit FlexFrame Bracket for easy mounting to frame tubing 25mm to 80mm wheter round, oval, triangular, or square Also features 360-Degree rotation providing the ability to better fit and align with a bike frame"s specific geometry