This is a dual channel transmitter that is activated only after entering a suitable combination. The unit is designed for installation in indoor or outdoor locations, providing high security as the transmitted code changes with each transmission session. The estimated transmission range is 200 meters in open space and 35 meters indoors. The unit is designed for a battery life equivalent to approximately 2 years of operation with 10 transmissions per day. Power: 6 Volt DC. Uses 2 pcs CR2032 Li battery. Battery life: 2 years (4 operations per day). Frequency: 433.92 MHz +/- 75 KHz. Transmitter power: 1 mW. Data format: standard. Operating temperature: -20°C to +55°C. Password number: 0-8. Waterproof rating: IP54. Material: Plastic + Metal. Color: Black + Gray. Package contents: 1 x Keypad, 1 x English Manual. Only the above package content is included; other products are not included. Note: Lighting and different displays may cause slight color differences between the item in the picture and the actual item. Measurement error allowance is +/- 1-3 cm.