Apparatus including a carbon-carbon composite pressure plate (32, 42) having a friction surface (33, 43) on one side thereof, a non-friction surface (37, 47) on the opposite side thereof, and a body (39, 49) between said surfaces. A wear pin housing (36, 46) containing a wear pin retainer (35, 45) is located in the pressure plate body (39, 49), the wear pin housing opening to the non-friction surface (37, 47) but not opening to the friction surface (33, 43). A wear pin (31), preferably made of carbon-carbon composite material, is located in the wear pin retainer (35, 45). The wear pin retainer (35, 45), which may be made of carbon-carbon composite material, is held in place in the wear pin housing (36, 46) by the interaction of threading in the wear pin housing (36, 36) and threading in the wear pin retainer (35, 45) and optionally also by a carbonizable resin adhesive located between the wear pin housing threading and the wear pin retainer threading.