Kryptonite Keeper Chain Lock Handy chain lock from Kryptonite with 4 mm thick links. The nylon cover is durable and weatherproof and ensures that the frame of your bike is not damaged. The combination cannot be reset after you have chosen it, so remember it well. Specifications: Color: black Material: steel, nylon Length: 65 cm Thickness of links: 4 mm Number code: 3 digits