This lock is the highest security Kryptonite U-lock available, featuring a 16mm Kryptonium steel with double deadbolt design. Includes three stainless steel keys - two standard "I" keys and one LED lighted key Oversized hardened steel sleeve over cross bar for double security Hardened MAX-Performance, 16mm steel shackle resists bolt cutters and leverage attacks Transit Flex Frame Bracket fits on the adjustable spline and allows for multiple off-set fitments to better align the lock for transportation Hardened deadbolt locking for extensive holding power Higher security disc-style cylinder Security Rating: 9 out of 10 Advertised Weight: 4.35 lbs Diameter: 16mm Length: 8 ins Lock Style: Keyed Shackle Width: 4.0 ins