Simson Sure ring lock The Simson Ring Lock Sure is very strong and can be used on almost any frame. The lock is ART-2 approved and can therefore be used as an approved lock for almost any bicycle insurance. The ring lock can be mounted on the frame tube with the Simson ring lock mounting set, but the lock is also suitable for top bolt mounting. The lock is supplied with two keys. Specifications: Color: black Material: steel/plastic Quality mark: ART-2 Type of lock: keys Diameter bar: 10 mm Contents: 1 Ring lock 2 Keys