10 Main Shaft Gears # 210802 for a MOORE-O-MATIC by LINEAR model XX133 It drives the main sprocket shaft . Recently inspected and is in excellent condition, no problems. This is a New old stock, gears only, Does not include any other attachments or fasteners. Gear measurements: 2 1/4" across, 1" high, 20 teeth,tooth 5/8"high, hole 1/2" warranty 1 year buyer pays shipping on any warranty While Supplies Last This gear is a dual purpose part, 1st it transfers the power from the motor to the door, 2nd. it is made to strip out and fail in the case of a severe malfunction in the door system saving the door operator from further damage. And any moore-o-matic door dealers that still have Stock left on the shelves And want to sell contact us Were always looking for old stock.stk(317)A4!