The Wartenberg wheel is a small device with radiating sharp pins. It was designed to test pain sensitivity. In the bedroom you can use it to play doctor or as a toy on its own. The wheel stimulates blood flow to the place of exposure to needles and amplifies the excitement.
Lay your partner down comfortably and slowly drive the Wartenberg wheel over their body. Start with hands and feet, then move to the back, neck and buttocks. Be careful with the more delicate parts of the body: breasts, nipples and genitalia. Proceed to them only when you both realize that the experience is pleasant. Try blindfolding to increase the sensation.