The Simson Ringslot Sure is very strong and can be used on almost every frame. The lock is ART-2 approved and can therefore be used as an approved lock for almost every bicycle insurance company. The frame lock can be mounted on the frame tube with the Simson frame 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 Hallmark: ART-2 Type of closure: keys Diameter rod: 10 mm Contents: 1 Ring lock 2 keys