Review on ARCELI KY 019 Channel Module Arduino by Carlos Phillips

The first one opened seemed to work, judging by the LED, but the switching was inaudible and the multimeter confirmed no continuity on normally open, although it should have been. The next two didn't even light up, but the last two worked fine. I tested each relay multiple times on the breadboard and placed different relay modules in the same spot. Another check suggests that the parts will work and the board itself is probably faulty. I haven't tested this, but I suspect it's correct, so it's not a waste of money, but hardly acceptable.