This is a WiFi verison relay board with optically isolated inputs and temperature sensor port and enclosure. Very powerful and easy to use. You can easily control this relay board by your computer or smartphone using WiFi. The communication way also can be changed easily. Remove the WiFiBee module instead with a BluetoothBee, it becomes a Bluetooth relay. It will be a USB relay when you plugged a USBBee. Very convenient to use.
The TSIR04 provides four volt free contact relay outputs with a current rating of up to 10Amp each. The module is powered from a 12VDC power supply. The DC input jack is 2.1mm with positive core polarity, The relays are SPDT types.