Designed for swim training, either in the pool or open water. The jammer lifts your hips up like a wetsuit and helps you find the right position in the water. You will achieve the same effect as using a pull buoy, but it allows you to kick and turn naturally. The jammer has a base of extremely flexible GLIDESKIN neoprene. 3mm on the back and 5mm on the front. It provides great mobility and minimum water resistance. Drawstrings at the waist. Unisex model.