All rubber construction *** Measures 2 1/2" x 2 1/2" x 1 3/4" tall *** This is held in place by the same bolt that fastens the handlebar to the fork stem, the bolt goes through the loop under the pad that is located off center under the pad. The second photo shows the location of the loop *** The bicycle this came from was designed so that the handlebar unit fastens around the outside diameter of the fork stem threads which extend above the steering tube and this rubber pad is designed to cushion that area