The LiftMaster 41A4371 Belt Cap Retainer is a genuine replacement clip designed for LiftMaster and Chamberlain belt‑drive garage door opener rails. Its primary function is to secure and guide the drive belt at the end of the rail, helping keep the belt properly seated on the pulley during operation. Replacing a worn, broken, or missing retainer restores correct belt alignment, reduces the risk of belt derailment, and supports smooth door travel on compatible residential belt‑drive systems.
This part is used on select LiftMaster/Chamberlain belt‑drive models that specify 41A4371 in their parts diagrams. Installation is straightforward: disconnect power, relieve belt tension per your opener’s manual, snap the retainer into position on the rail assembly, and re-tension the belt to the manufacturer’s guidelines. No programming is required after replacement. For compatibility, match the part number to your opener’s service manual or rail label to ensure the correct fit for your belt rail assembly.