The Hiplok is the world"s first bicycle lock developed specifically to be worn on the body. It’s a seriously strong piece of kit with a hardened steel chain at its core and a Sold Secure accreditation. All Hiploks are fully adjustable - one size fits all 26" to 44" waist. The locking mechanism uses a disc tumbler system which is almost impossible to pick as opposed to a pin tumbler mech which can be bumped or picked quickly the main padlock uses a hardened shackle which is resistant to bolt croppers and hacksaw attacks. The lock body is stainless steel with a unibody moulded case of super tough nylon. The chain is case hardened CrMnTi steel alloy which again is resistant to bolt cropper and hacksaw attacks. Its rated Sold secure in the uk. http://www.soldsecure.com/. With Hiplok there’s no need to attach or hang a lock to your bike while you’re riding, meaning you don’t spoil the clean lines of your machine, or scratch your frame. And should you need to carry your bike up a flight of stairs or bunny hop a high curb, the fact that you don’t have your lock on your bike makes it lighter and easier to maneuver also.