This super strong lever-release suction cup is specially designed to fit the OptiMALE Endurance Trainer’s proprietary screw-on end cap and powerfully adheres to any smooth, non-porous surface. This suction cup was designed for hands-free use of your OptiMALE Endurance Trainer variable pressure stroker and is ideal for shower/bath use. The strong adjustable arm swivels and bends for custom positioning, and locks into place. Includes complete instructions for use.