LING'S SHOP 1Pc Wireless RF Remote Control Transmitter For Garage Door Gate 315MHz/433MHz (315MHz) Working voltage:DC12V (27A/12V battery x1, Included) Transmitting frequency:315/433MHZ (Selectable) Emission Distance:20-50m (Open area) Encoding type:fixed code(1527 1538) Oscillation resistance:4.7M