Chamberlain - 950 CB, 953CB. LiftMaster / CHAMBERLAIN and Sears Craftsman (Openers with aRED Smart Button only). ALL LiftMaster, CHAMBERLAIN, Sears Craftsman MachinesManufactured between 1997 - 2004. or - Any LiftMaster, Chamberlain or Sears Craftsman Machines that have one of the following PART NUMBERs on the end panel(you may have to pull off a light cover to find this part number).
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