Cloud Relays With Optocoupler Isolation 8 Channel Relay Module Plc Relay Dc 5V Go to amazon.com Related posts 11 best isolation relay hvac for 2022 Featuremodule size:13.45cm * 5.27cm.uses:1,support single-chip control.2,industrial areas.3,plc control.4,home intelligent control. Descriptionthis is an optocoupler 8 relay module dc 5v.