The LiftMaster 29B129 Belt Connector is a genuine OEM replacement component for LiftMaster belt-drive garage door openers. This connector secures the drive belt within the rail system—either joining the belt ends or linking the belt to the trolley/carriage—so the operator can move the door smoothly and quietly. Use it during belt replacement, rail service, or when repairing a damaged belt link to restore reliable operation and correct belt tracking on compatible LiftMaster belt-drive operators.
Compatibility depends on the opener model and rail type; install only on units whose parts diagram or owner’s manual specifies part 29B129. For installation, disconnect power, release the door via the emergency handle, and follow the model-specific routing steps to thread the belt through the rail and trolley. Fit the belt connector in the correct orientation, then use the opener’s tensioner/turnbuckle to remove slack without overtightening. After reassembly, reprogram travel limits, verify force settings, and test the safety reversal and photo-eyes. This LiftMaster 29B129 Belt Connector is an ideal replacement part for residential service or dealer maintenance where an exact-match LiftMaster belt connector/link is required.