Made of solid cast iron with a 2-inch center hole fits any Olympic bar with diameter 2 or less; Can be used with 2 dumbbell bars tooAll plates features a durable, black baked enamel finish to prevent the plates from rust and corrosion without any unpleasant odorEach plate has 3 large openings with strips on them for easy grip. Labeled in both LB and KG for easy recognitionWeight plates can be used to perform muscle strengthening exercises and endurance training, or to increase flexibility and balance2.5 Pounds, 5 Pounds, 10 Pounds, 25 Pounds, 35 Pounds, 45 Pounds