Positive 5V: +5V positive supply, input or output GND: Ground, input or output P30 - P35: CH3 - CH8 control lines, high level effective CLR: Short CLR to restore module settings to factory defaults Blue Terminals: Connect to user load; compatible with 220V AC or DC equipment under 30V, within the relay's rated current capacity 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 Included: 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 error allowed is +/- 1-3 cm