Kryptonite's Evolution Mini 7 U-Lock may be a little guy, but it packs a big punch thanks to the 13mm hardened Performance steel shackle that resists bolt cutters and leverage attacks. Popular among urban cyclists and messengers, the Mini fits well in a pocket and locks up quickly thanks to the disc-style cylinder and "I" keys, one of which features a high intensity LED for locking and unlocking in the dark. The included flex cable lets you secure your wheels too. And, it includes the Transit Flex Frame Bracket so you get plenty of mounting options while you ride. The lock measures 3.25 x 7-inches.