The Universal LiftMaster 811L is a 2-pack remote control designed for Chamberlain garage door openers. It is battery-operated, with batteries included, and has a sleek black plastic design. The remote features one button, is compatible with the 811LM model, and operates on frequencies of 310, 315 MHz, and 390. This electronic entry transmitter from LiftMaster is a reliable and convenient solution for controlling your garage door opener.
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