This is a dual channel transmitters that are activated only after having entered a Suitable combination. The units are designed for installation in indoor or outdoor locations that ensures the utmost security because the transmitted code is changed at each transmission session. The estimated transmission range is 200 m in open space and 35m indoors . The units are designed to ensure battery life equivalent to an estimated 2 years of oper-ation considering 10 transmissions/day. Power:6Volt DC 2PCS CR2032 Li battery Battery life:2 years(4 times operation every day) Frequency:433.92MHz+/-75KHz Transmitter power:1Mw Data format:standard Work temp:-20~+55 centidegree Password number:0-8 Water proof level:IP54 Material:Plastic + Metal colour:Black + gray Package Contents: 1 x Keypad 1 x English Manual Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm. Note: 1. Please allow 1-3 mm error due to manual measurement and 1-3g weight error make sure you don't mind before ordering. 2. Due to the lighting of the photos and the difference of monitors, the pictures may not reflect the actual color of the real item. Please make sure you don't mind before ordering, thank you! About Shipping: 1.please pay attention to your delivery address such as: name, street, house number, doorbell/email without name, etc. is correct, or the order will not be delivered correctly. 2.All items will be shipped within 3 business days after the payment is received. Most times you will receive them within 8-12 days then. The specific delivery time is depend on circumstances. 3.During the shopping process, if you have any questions, please feel free to consult us, we will reply you within 252 hours Hope you have a pleasant shopping experience!