Liftmaster 41C4398A - RPM Sensor Assembly. 1A4903, 41C3005, K75-16426, 41B3000, 41C4398A, 41C4398, 41C4398-1. This RPM Sensor features a five bladed photo interrupter. For use with various LiftMaster® and Chamberlain® Garage Door Openers; manufactured after 1995.
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