Surface-mounted security bolt, model crr07, made of steel with a gray finish, 105l/50 mm, with 3 master keys, 105 mm plate and 50 mm round cylinder, designed to reinforce security by installing on any type of door. being reversible, it is non-handed and can be operated from both inside and outside using a key through the cylinder, with identical master keys of type b serrated edge. made of steel, includes screws.