CycleBeam LED Illuminated Combination Bike Lock - Best Bike Lock for Night Riders (TM) IBL-12 Best Lock for Night Riders: An LED is built into the dial. When the button is pressed, the dial is lit up for 15 seconds, enough time to unlock your bike in the dark. Self Coiling: The cable will coil back to a circle so you can mount it back to your seat post or put it back to your bag. Lock and Unlock with a Combination: You don't need to carry a key. Set and reset your own passcode with ease. Comes with a mounting bracket for bicycle Length: 4 ft Diameter: 1/2 inch (with protective vinyl coating), 1/4 inch (without protective vinyl coating)