4 Channel 5V Relay Shield Module

This is exactly what I wanted. Simple low voltage control for 4 standard 110V outlets (of course light duty use only). Direct control by parallel port data pins on old PC.

I use this relay board because, the power required to activate relays is supplied by external power supply. I want to minimise the current load on the raspberry. I needed DPDT relays so i used two in parallele Very fast delivry

Excellant quality product with creepage slots and opto-isolated inputs. Far better tahn the cheepies direct ordered. RobotShop is #1. AND when they say you will have it in 3 days--that's when you get it! Thanx RobotShop!

Being in engineering I was impressed that it has the high-voltage isolation grooves cut into the pcb and not just the isolation in the front-end. This is the proper way to do it on the power side of relays to prevent AC creep. (I have not tested their isolation characteristics though)

I bought one of these for use with an Arduino Uno, to switch various model railroad-related loads. So far so good!