The HIP ROTATOR is a training device designed to improve your freestyle and backstroke technique. It is a belt with two paddle fins attached to it by Velcro straps. For freestyle, attach the belt to the belt, then attach the fins at the 3 and 9 o'clock positions. For backstroke, attach the fins at 2 and 10 o'clock. This simulator helps you identify the moment your hips and trunk rotate during the stroke. If you do not turn your body enough or in time, you will hit the fin with your hand during the stroke. The trainer is great for athletes of all ages and skill levels. The belt is adjustable to fit any waist circumference.