Liftmaster 41B8861 24V Absolute Encoder RPM Sensor — Garage Opener Replacement for DDO8900W, 3800P, 8500W

24V absolute encoder and RPM sensor for Liftmaster garage and dock door operators, model 41B8861 (also referenced as 041B8861). Replacement part often listed under alternate numbers 41A6408 and 041A6408. Compatible with the following units: DDO8900W Light-Duty Commercial Dock Door Operator; 8500W DC Battery Backup; Wall Mount Wi-Fi Garage Door Opener 3800P. Also compatible with CSW24V and CSL24V.