The LiftMaster 33LM color-coded commercial garage door/gate operator remote control transmitter from Garage Door Supply Company is a 390MHz three-button remote. Use it with a LiftMaster 423LM 3-channel receiver for 30MHz fixed-code LiftMaster gate operators and commercial garage door openers.
A visor clip and 12-volt battery are included. The 33LM LiftMaster remote is compatible with 390MHz LiftMaster, Chamberlain and Sears gate or commercial garage door openers. The three-color remote three-button is a nine-position trinary dip switch remote that has 19,683 codes per channel.