Features:*It contains 1 * Sonoff RF Bridge 433 + 1 * Sonoff 433Mhz PIR2 PIR Sensor + 1 * Sonoff 433Mhz DW1 Door Sensor.*App Support: Free iOS and for Android mobile App eWeLink.*Convert 433MHz RF Remote controller to App via WiFi.*Make 433MHz RF devices App remote controllable.*Supports adding up to four 433MHz RF Remote Controller/ RF Curtain Switch / RF Alarm.*Supports control up to sixteen 433MHz RF devices.*Remote ON/OFF: Turn connected 433MHz RF devices on/off remotely over Wi-Fi or mobile network from anywhere on the App.*Timing: Supports scheduled/countdown timing tasks to turn on/off 433MHz RF controlled devices at specified time.*The receiving supports fixed code 433 frequency, like PT2260, PT2262, PT2264, EV1527, etc.*Voice Control: Compatible perfectly with Amazon Alexa and for Google Home.*Receive alarm push message from 433MHz PIR sensor, door window alarm sensor.*PIR2 Sensor is dual infrared. Double temperature compensation technology.*PIR2 Sensor is ultra-low power microprocessors. Robust and durable, suitable for homes, offices, sheds, garages etc. Easy installation and set-up, wall-mounted.*DW1 Door Sensor is ultra-low power less than 1??A quiescent current magnetic dedicated microprocessor. Built-in antenna provided.*DW1 Door Sensor supports wireless frequency of 433.92MHz and 200m wireless transmit distance.Sonoff RF Bridge 433