1. Adopt advanced infrared detect technology. 2. Infrared sensor detects motion and sends a signal to the receiver. 3. Wireless installation, just place the sensor at the entrance. 4. Easy to install and no electrical wires to install. 5. Unique appearance design, evoking an aesthetic feeling. 6. Detector requires 9 volt heavy duty battery(not included). 7. Receiver requires 2xAA batteries(not included). 8. Perfect for home, office, hotels, jewelry store etc..

http://olla.gr/yf-0155-good-safe-wireless-electro-guard-watch-remote-detective-system-kit-for-home-office-1-x-receiver-1-x-detector/