M-Wave ring lock The ring lock is a very practical way to lock your bike. It is attached to the frame of your bike and blocks your rear wheel. Despite this, we recommend that you use a chain lock in combination with a ring lock. This allows you to secure your bike to a fixed object such as a lamppost or a bike rack. Specifications: Plug-in option: no Opening width: 56 mm Weight: 415 grams Color: black Material interior: steel Material casing: plastic Mounting: on frame Contents: 1 Ring lock 2 Keys