plasticImported1.Premium Quality: The swim hand paddles are made of PC Material, they are light weight, does not impose an additional burden on swimming. They are durable and not easy to bend, feel smooth.2.Ergonomic DesignHand paddles with convex design, provides increased traction with the water. Hand paddles have many drainage holes and water channels, low-impact will allow you to build muscle safely.3.Adjustable Straps: Straps are made of silicone material, they won't hinder the blood flow in palm. The length of the shoulder strap adjusts the palm to the most comfortable state.4.Various Uses: Help you practice your swimming, like freestyle, backstroke, breaststroke and butterfly. Suitable for swimming beginners to improve swimming skills and enhance arm strength.