Wartenberg Wheel

The Wartenberg wheel is a revolving wheel with handle-mounted sharp pins. Dr. Robert Wartenberg created it initially, which was used to examine skin sensitivity and nerves. However, it is now more of a sex toy and is seldom ever utilized in medical situations. This device's prickly wheel can be rolled or dragged across the skin to provide a variety of sensations, including prickly and tickling. The most common application of it is in sensation play.

More About Wartenberg Wheel

Depending on how it is used, a Wartenberg wheel can produce a variety of feelings. A very mild tickling sensation can be made by gently rolling or dragging the gadget over a sensitive erogenous zone.  An erotic but slightly more uncomfortable sensation can be created by applying additional pressure. Pushing too hard could result in wounds, abrasions, punctures, or bruises, so proceed cautiously.