Liftmaster door fob TX4EVF / TX2EV / TX4EV / TX2REV / TX4REV / TX4REV-F 868Mhz.

Frequency - 868MHz. Transmit distance - 25-50m in open space. No walls, no doors, no trees or any other obstructions. There can be many reasons why the item is not working which are Lack of programming experience;.

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