U4/Bike Lock Chain Lock Bike Bicycle Diameter 22mm 【Extra Thick & Extra Thick】Diameter 22mm Extra Thick Wire 10mm x PVC Coat 12mm x Nylon Cover protects your precious car from criminals. We use even thicker ultra-thick wire to pursue security. The main purpose is for customers to use the product with more peace of mind. 【Copper Cylinder & Key】Equipped with a copper key cylinder that automatically springs back. Excellent anti-mite/rust/waterproof properties. The keys are also made of copper, making them difficult to duplicate, wear-resistant, durable, and can be unlocked smoothly forever. This product is safe and convenient to use because it is high-strength, accurate, rust-free, luxurious, and durable. 【Dust-proof Shutter Design】A dust-proof shutter is designed to be easy to use and less likely to clog, as it is common for dust and sand to get stuck in the shutter and make it difficult to open! 【Easy to Open and Close】The key can be used on both sides, regardless of the front or back. When locking, simply insert the tip into the keyhole! When unlocking, insert the key, turn it around, and pull out the tip! The operation is simple and not troublesome. The length is 1200mm and is applicable to a wide range of applications such as motorcycles, scooters, bicycles, and office doors!