1、Anti Interference: Relay module has an optocoupler isolation components with high interference resistance and very helpful. 2、APP Control: This relay module sends commands via Bluetooth APP to control the relay to turn on and off. For Android Bluetooth APP is provided, you can also control the relay with your own APP by sending a simple command. 3、Light Weight: This relay module is light weight, portable and easy to install, Suitable for IOS and for Android 4.0 and for 5.0. 4、Short Response Time: Our 4 channel relay module has diode current depletion protection and short response time. 5、PCB Material: The relay module has an adjustment distance of 10 meters without obstruction and is made of PCB material with exquisite craftsmanship, safety and practicality and long service life. Item Type: Relay Module Material: PCB Connection: Bluetooth BLE 5.2, 2.4GHz-2.48GHz unlicensed ISM band. Commands: For Open, for Close, for Delay, and for Open and Close, commands can be modified. Size: Approx. 63 x 74 x 19mm / 2.48 x 2.91 x 0.75in Maximum Load: 10A 250VAC, 10A 125VAC, 10A 30VDC, 10A 28VDC, 10A 12VDC. 1 x 4 Channel Bluetooth Relay Module