Designed as a five-digit resettable bike chain lock, this unit offers keyless operation and a broad set of possible combinations. The locking mechanism uses a zinc alloy cylinder paired with a 0.24 in. steel chain, which provides a level of drill resistance and tamper deterrence compared with lighter locks. The chain is protected by a durable polypropylene fabric sleeve that resists scratches and wear, helping prevent damage to the bicycle frame during use. The combo system allows you to choose and reset your own code, with up to 10,000 possible combinations and a default of 00000 for initial setup. When handling the lock, you will find it straightforward to lock or unlock without carrying a key, and you can reset the code as needed. In terms of size, the chain measures about 3.2 ft. in length and the lock head has a diameter of roughly 1.25 in. enabling you to secure the bike to posts, rails, or other solid supports. The unit weighs about 1.45 lbs., making it portable for everyday use. It is suitable for securing 2-3 bikes together or locking to fixed structures such as trees, gates, fences, rails, or thick poles. If wheel gaps are smaller than the head diameter, threading through the wheel may be impossible. Color: Black.