Kiefer 690403-Blu Contour Pull Buoy, 9-Inch, Blue Pull buoy is made from contoured EVA foam, offering maximum flotation and a comfortable fit Asymmetrical shape allows for flotation adjustment to vary workout resistance and stroke technique Great for training for the individual swimmers, aquatic programs and swim teams Hold buoy between the thighs to provide buoyancy to lower body while doing arm pulling drills and stroke correction Fun and easy to use