Dumbbells can be used for a variety of training - target arms, chest, back, shoulders and core. Cast Iron core for extra strength and reliability while the solid metal chrome finish contoured (ergo) handles designed to fit comfortably. Hexagon shaped dumbbell heads heads help prevent rolling and and provide for easier storage. Sold Individually and in Pairs, please double check when purchasing. Backed by HulkFit 2 year warranty.