They're a little bit bigger than the usual choc-block style connector strip, but I've used a few of these which seem to work well. They also have the advantage that because they're spring-loaded, they are much less sensitive to vibration than screw terminals. Also, each wire goes into its own little socket so no need to twist wires together as you do with choc block - always end up chasing odd strands, trying to balance the lengths of wires, etc, when I use them. Don't know if anyone sells them in smaller quantities.