The spencer paddle has holes drilled into the surface to increase the rate at which it can be swung. The less wind resistance there is with a paddle, the more forceful the strike will be. This increases the pain which also increases the pleasure created by the entire process. Typically, spencer paddle sex toys are wooden. However, paddles of any material may have holes drilled into the striking surface, like the Sportsheets Acrylic paddle, would qualify as a spencer paddle.