PowerBlock SportBlock 9.0 Adjustable Dumbbells - 40 lb. Add-On, The PowerBlock Sport 9.0 Set is the most compact dumbbell available. The small size of the PowerBlock keeps the weight concentrated closer to your hand making the dumbbell easier to control and balance.
The PowerBlock Sport 9.0 expanded to 90 lbs with Stage II Kit will replace 28 pairs of dumbbells or 2565 lbs of free weights and can be expanded again to 130 lbs per hand with the Stage III Kit. Increments achieved with the Sport 9.0 Stage I are 2.5 - 90lbs. per hand.