Hydro-Fit 166 Medium Blue Classic Wave Belt with Buckle Closure Spend more time working out and less time adjusting your buoyancy belt. Sound impossible? Not with this belt. Our Classic WAVE Belt® features a quick-release buckle strap for a secure fit. Made of soft and durable EVA foam, the Classic WAVE Belt forms to the natural shape of your body. Its unique contour shape balances buoyancy evenly around your torso, enhancing correct posture and body alignment.