2PCS Sprocket Coupling Black for LiftMaster Chamberlain Garage Door Opener 25C20
Fit for Liftmaster models 1000SD, 2000SD, 1000SDR, 2000SDR, 2110, 2220;. Fit for Chamberlain models 4600, 4620, 4640, 9902, PD420, PD460-2, 9950, and more. 【 Simple Installation 】 :If the Garage door makes noise but cannot be opened, it may be that there is a problem with the coupler.