Bike Chain Lock 4feet/120cm Long Heavy Duty Anti-Theft Motorcycle Chain Locks Security 10mm Thick Chain with Bright-Colored Lock,Durable Moped Lock with 4 Keys for Bicycle,Scooter(7.28lbs)

【Cut Resistant U Lock】Only 25mm inner diameter is smaller than ordinary u-shaped locks, making it difficult for hydraulic shear to enter the lock and preventing it from being cut easily. Bright-colored lock on your bike could be enough for them to decide to skip your bike and go on to the next one.
【φ48mm Steel Ring】There’s a steel ring on one side and a free steel ring. It has many ways to use it. Made of 3T manganese steel materials and heat treatment hardening technology. 10mm chain is thick enough to withstand 10KN tension and 20KN shear force.
【4 Unique and Ergonomic Keys】One for daily use, the others are self-assigned and difficult to duplicate or wear out. The key can only be pulled out after locking to prevent key loss. Made of hard and durable stainless steel, never bend or twist.
【Pure Copper Crescent Lock with Cover】Used normally after being damaged and hard to replicate. The keyhole is equipped with a cover to make it waterproof and dustproof, which can prevent damage to the keyhole and extend the service life.
【Nylon Sleeve Cover】23 Chains are wrapped in the protective nylon sleeve cover, protect the chain from rusting and scratching, and also prevent damage to the bike. Secure it with rivets to prevent it from shifting.