Positive 5V: + 5V positive power supply, input or output GND: power ground, input or output P30 - P35: CH3 - CH8 control lines, high level effective. CLR: CLR short and to the module power settings to restore the factory settings Blue Terminals: Connect user load, you can use 220V AC, or less than 30V DC equipment, which can not exceed the current standard load relay. Each relay has a normally open contact, a normally closed contact and a common contact, relay timely, public contact and normally open contact conduction; relay released, public contact and normally closed contact guide pass.AH893 Material: plastic, metal color: red Size: 70X 50mm Package Included: 3x LAN Ethernet 2-way Delay Time Switch Relay Board TCP/UDP Controller Module Only the above package content, other products are not included. Note: Light reflection 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.