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.
About the Expansion Kits:
The U-90 comes in 3 stages. Stage I is the base unit and can operate independently. Stage II units include the 50lb – 70lb kit and 70lb – 90lb kit. Both need the base and prior expansion kit to operate. Each of the two add on weight kits in Stage II are sold separately. The final kit is the 90lb – 125lb kit. This will also need all previous expansions to function.