OnGuard's Doberman is a strong self-coiling steel cable secured with OnGuard's stout X2 double-bolt lock, which resists picking, drilling, and cutting. The cable has a tough vinyl cover which protects your bike. For convenience, the Doberman comes with a mounting bracket so you can carry the lock on your bike. And you get five keys, including OnGuard's Microlight key which has a built-in light.