Positive 5V: +5V power supply, input or output GND: Power ground, input or output P30 - P35: CH3 - CH8 control lines, high level active CLR: Short CLR to restore module to factory settings Blue Terminals: Connect to user load. Compatible with 220V AC or DC equipment under 30V, within relay current rating. Each relay features one normally open contact, one normally closed contact, and one common contact. When activated, the common contact connects to the normally open contact. When deactivated, the common contact connects to the normally closed contact. Material: Plastic, Metal Color: Red Size: 70 x 50 mm Package Includes: 1 x LAN Ethernet 2-way Delay Time Switch Relay Board TCP/UDP Controller Module Note: Lighting and display differences may cause slight color variation between the image and actual item. Measurement tolerance: +/- 1-3 cm.