Da Vinci Dumbbells are made of cast iron and are coated with Neoprene for durability, comfort, and to help protect you, the floor, and other fitness facility and equipment in case of drops. The Neoprene surface provides for a comfortable and sure grip that won’t slip due to sweaty hands. These dumbbells are the ideal athlete companion to help tone arms, shoulder and back, and the hexagonal shape prevents the dumbbells from rolling when put away. Choose from a variety of sizes and colors. Sold in pairs so you will receive 2 dumbells in one package.