These are flat-back single jump cups for use on double or triple jumps. An ingenius mounting system takes away the pain of figuring out where to mount the jump cup so that the bar will be at the correct height when it's set. All you need to do is drill a hole at the correct height, such as 24", insert the pin on the back of jump cup into that hole, then fasten a screw through the pre-drilled hole in the jump cup. The jump cup will be at the perfect height. The pin also holds the jump cup in place, so the jump cup won't "spin" even though you are just using a single screw to fasten the cup.
Packaging: Clip and Go Flat-back Single Jump Cups come in a package of 20 for the price shown. Screws are not included.