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  • 14mm MAX-Performance hardened steel shackle resists bolt cutters and leverage attacks; hardened oval crossbar design is stronger than typical round tube
  • Double deadbolt locking mechanism for extensive holding power that provides added protection against twist attacks
  • Disc-style cylinder delivers a high level of security; rotating dust cover helps protect cylinder
  • Includes versatile mounting bracket for easy transportation; anti-rattle bumpers reduce noise during transport
  • Comes with 3 keys, 1 of which is lighted with a high intensity bulb and features a replaceable battery
  • Eligible for Key Safe Program; register your key number with Kryptonite for easy replacement of lost or worn keys for a minimal fee
  • Kryptonite rates the Evolution Series 4 U-lock an 8 on a 10-point system with 1 being simple, deterrent security and 10 being extreme security


View all Kryptonite U-Locks

REI membership


Best Use Cycling
Lock Style U-lock
Lock Type Key Lock
Lock Thickness (mm) 14 millimeters
Material(s) Steel
Dimensions 9 x 4 inches
Mounting Frame
Weight 3 lbs. 12 oz.

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