【433 MHz Required】 This door sensor only works with a 433 MHz 1527-based alarm host. We have introduced it for our wireless GSM & WIFI security alarm system. If you purchase an alarm system from elsewhere, please check the code carefully before purchasing. 【Intelligent Design】 Polished white body, high-quality sensitive button, intelligent size, weight: 25 g, dimensions: 30 mm*67mm*15mm (Part A) and 11 mm*44 mm*13.5 mm (Part B). Users can install it anywhere, such as in a garage, basement, garage, office, etc. E.g., door, window, drawer, closet, bathroom, etc. 【Intelligent Coding】 When the battery is low, the door sensor will provide low battery information for the alarm (PGST Wireless 2G and WIFI security alarm system, sold in our store). For other brands of alarm hosts, it may display general alarm information, or users may need to check with the indicator light (flashes frequently when the battery is low). 【Easy Maintenance】 The door sensor uses an alkaline button cell battery. When the battery is low, it is easy to replace it online or via Amazon. It lasts approximately 1 year in standby mode, 6 months for home use, and 3-6 months for commercial use., Weight: 200.0 grams, Manufacturer: PGST