1, support work in the server, client, UDP mode. 2, work in the server mode to support four client connections. 3, support MODBUS protocol, support configuration . 4, support for online updates, very easy to customize the program. 5, to customize the device name, when the device does not have more time to record cumbersome IP number. 1. Supply voltage, 5V, not less than 1A current. 2. Two-way relay function of the largest single-way 2KW, AC load rated voltage of 250 volts, 10A current. DC load rated voltage 30V, current 5A. 3. The appearance of size 81 * 50 * 31 MM. 4. Operating temperature -40 - +80 degrees. you can customize the heartbeat packet time, reliability off recovery. is a high-performance -M3 core 32-bit Minicontroller (STM32F103C8) Size:81*50*31MM Material:Plastic + metal Colour:gray Package Contents: 1 * Board Delay Switch Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.