41AC050-2M is the receiver logic board for LiftMaster and Chamberlain AC Deluxe chain drive openers made from 2005 through 2015. It's a 315MHz board with a purple learn button. If your opener's ignoring the remotes or the board looks visibly damaged, this is the direct swap. Sometimes labeled as 41AC050-2 in older parts lists. These boards are model-specific though, so look up your opener and make sure the part number lines up. AC Deluxe chain drive only, not the standard chain or belt drive versions.