[Portable U-Lock]: The U-lock is made of lightweight but strong aluminum steel, the lock only weighs 563g, it is a portable size, so it's specially designed for cyclists who don't want to carry too much extra weight[Keyless and Safe]: With keyless design, you don't have to worry about losing keys and forgetting to carry them. 4 digits to set your own combination conveniently allows thousands of possible combinations. Prevent thieves from using the master key to unlock the lock.[Solid lock]: The U-shaped lock has undergone multiple heat treatment processes to increase its hardness and strength, and resist smashing, cutting, and violence.[PVC Coating]: The lock is covered with a thick layer of PVC material, which is not easy to crack at high temperature, slip-resistant, wear-resistant, and impact-resistant. The PVC coated protective cover protects the paint and surface of the bike from scratches.[Easy to use]: So easy to use, your kids can use the lock without worrying or dealing with them losing their keys. Suitable for indoor and outdoor: bicycles, motorcycles, glass doors, warehouses, patio doors, cabinets, tool boxes, luggage, fences, etc.