PowerBlock Series 50 lbs. EXP Set Adjustable Dumbbell has a weight range of 5-50 lbs and replaces 16 pairs of dumbbells in the space of 1. EXP means expandable and you can expand this set later to 70 lbs and again to 90 lbs with optional expansion kits. Includes two 2.5 lb adder weights per handle at no charge to micro-load weight adjustments. Patented compact design keeps your workout are neat & organized.