The Flex Series Urethane Sets from PowerBlock are the fourth generation of PowerBlocks. The Urethane coated weight plates offer the ultimate in smooth and quiet performance in addition to Flex technology (patent pending) in both the weight plates and the selector pins making for the most durable PowerBlock ever. The steel side colored rails are powder coat painted and are on both sides of each block. There no welded parts on the Urethane weight plates. Urethane Series products carry a lifetime home warranty.
The U-90 Stage I Set is expandable later to 90 lbs per hand with the U-90 Stage II Kit, and again to 125 lbs per hand with the U-90 Stage III Kit. The U-90 Stage I Set has a weight range of 5-50 lbs per hand and will replace 16 pairs of dumbbells or 825 lbs of free weights. Increments achieved with the U-50 Set are; 2.5, 5, 7.5, 10,15, 17.5, 20 25, 27.5, 30, 35, 37.5, 40, 45, 47.5 and 50 lbs per hand. The dimensions of U-90 Stage I Set are; 12.5" L x 7" W x 7.25" H