National Geographic Snorkeler accessories are constructed from materials at the leading edge of water-wear technology. The Heavy Duty Snorkeler Vest allows a snorkeler to comfortably rest on the surface or effortlessly glide through the water. The heavy duty adjustable waist and crotch strap allows for a wide range of sizes. The attachment D-Ring is perfect for holding your lanyard on the Nat Geo Fish ID Card. An attached whistle for a distress call if needed.