This is a LiftMaster 811LM 1-Button Remote.
Ideal for applications such as gated communities or commercial applications requiring a large number of remotes for a common entrance.
Dual 12-position DIP programming offers up to 4,096 codes.
Narrow band transmission on 3 simultaneous frequencies (310, 315, 390 MHz).
Compatible only with Security+ 2.0® commercial receivers and operators.