I have an insidious little device that is just perfect to isolate and crush the balls.. I place the cock and balls through the hole and then tighten down the knobs on the acrylic boards. I love watching the balls flatten beneath the glass, and I make it even worse by stimulating the cock. You see, as the cock grows harder, it pulls the skin taut in the crusher and makes the sensation more intense. And then I keep turning.. and he keeps whimpering.