In 1993 PowerBlock introduced the world's first quick-change adjustable dumbbell. Today we remain the only adjustable dumbbell found in the training facilities of pro sports teams, major colleges and universities and elite training facilities around the world. Set includes 2 dumbbell blocks (1 pair) plus storage rack. Compact - Just 12.5" in Length at 50lbs (12.5" x 7" x 7.25"). Convenient - Replaces up to 10 pairs of traditional dumbbells (5, 10, 15, 20, 25, 30, 35, 40, 45, 50) in 5 lb increments. Quick and Easy - Adjustability Ideal for supersets and pyramid loading. Convertible - Compatible with Pro Kettlebell Handle. Trusted by professional and elite athletes and their trainers. Proven performance and reliability. Grip is hard chromed knurled steel, 1.3" grip diameter, and 4.88" long. Weight plates are polyurethane coated steel, with a magnetic pin, rated for 500 lbs.