With A 5-Digit Resetting Combination, The Ndakter Bike Lock Is An, Duty Lock. SECURE RESETTABLE: Smart 5-digit resettable combination bike chain lock, much safer than other 4 digit locks. Easy to set your own personalized number combination STURDY DURABLE: It's hard to break through as the lock cylinder of the bike lock is made of zinc alloy. The bicycle chain lock is made of 0.16 inch alloy steel which is drill-resistant and anti-tech unlocking SCRATCH-PROOF FABRIC PROTECTION: The bicycle chain lock is wrapped by a high quality polypropylene fabric, which is scratch-proof and wear-resistant, anti-hot and anti-icing hands; it protects the chain and prevents it scratching your bicycle frame, long lifespan CONVENIENT TO USE: Combination locking mechanism provide keyless convenience and set your own password by easy steps. With keyless convenience lock, you don?t worry about lost the key and forget to carry it. Code design saves you from the hassle of carrying keys. The code is resettable - there are 10,000 combinations you can set, which makes the chances to crack the code only 1/10,0000. The default code is 00000. NOTE: When setting your new password, please first keep the digital wheel in the correct unlock password state before turning the reset disk. Turn the reset disk 90 to set a new password. MULTI-PURPOSE: The chain lock is 3.2 feet, long enough to lock 2-3 bikes together, or lock your bike to a tree, gate, fence, railing, thick pole and others. The lock can also be used for motorcycles, scooters, skateboards, grills, ladders, doors, lawnmowers and many others. NDakter provides a one-year warranty, we'll either replace it at no cost or issue you a full refund. NOTE: The male end of the chain is 1.25" diameter, you'd better confirm the gap of spokes/hole to wrap through before your purchase. Otherwise, you can only lock your scooter by winding instead of the gaps in the wheels.