The Aqara Door and Window Sensor P2 is a Matter over Thread version contact sensor with smart home compatibility options such as Apple HomeKit, Google Assistant, and Amazon Alexa. This sensor includes a sensor main unit, round magnet, flat magnets, and stickers in the box, making it easy to set up for monitoring doors and windows. With operating temperatures ranging from -10 °C to 50 °C and humidity levels of 0 to 95% RH, this sensor is designed for reliable performance. The compact dimensions of 77 × 22 × 22 mm for the main unit and 36 × 11.5 × 7.3 mm for accessory units make it suitable for discreet installation. Made by Aqara, this door and window sensor offers convenience and security for your smart home setup. Perfect condition cleaner ready to go never use never installed. Seller has perfect readings and ships fast and secure. I’ve been on eBay for over 28 years. Have fun!