This set includes a sturdy U-shaped lock and chain, perfect for security. - Type: Chain lock - Color: Black - Number of keys: 4 - Lock shape: U-shaped 1m As you can see from the photos of the keys, it's clear that it hasn't been used. This is a very strong chain. The 4 keys are convenient and helpful. I bought it because it had 4 keys, but the length didn't fit my bike parking spot (T_T) It's a beautiful item. Thank you for looking.