Finis Tech Toc Finis Hip Rotation AidDescription The Finis Tech Toc is a training tool worn around the waist that provides swimmers with instant stroke feedback and ensures proper hip position during all four strokes. The Tech Toc utilizes a ball bearing and acoustic amplifiers in order to create a sound as the device is tipped from side to side, this audible feedback lets swimmers hear and feel hip movements and notify them of proper hip rotation and undulation. Utilizing the hips and