The Hiplok lite is a fairly high rated security device for cycles, which, whilst cycling, is worn around the waist like a belt, secured by Velcro. simply take it off, put it around the bike and a railing or other immovable object, and lock it on. It also has a reflective strip. My only reservation is that it could benefit from being slightly longer, but the it would not be so wearable.it certainly saves lugging a chain and padlock around, and is rather better than a ‘ D ‘ lock.comes with three keys.