When the bolts are fully tightened, the captive washer will not touch the base leaving a gap. This prevents the use of mere tiny paraphernalia without the use of a crimped wire in these terminal blocks. I was going to attach phone cords end-to-end and the clamp would not be tight enough to hold the wire. Otherwise I think they would be fine. I received my order without 2 pieces and the 3rd one is broken so I'm sending the whole batch back.