Rocketlok 5-Pound Handle Set (Pack of 2) Customize you set of Rocketlok dumbbells by using the 5 pound handle and adding the (4) pack of either 2.5 or 5 pound weights Weights interchange with Rocketlok curl bar and works with 100 pound set The Rocketlok dumbbell is more compact and balanced, and they feel extremely solid. Lets you rapidly adjust weights in seconds Free weights, specifically dumbbells, used in controlled, slow movements, cannot be beat for effectiveness, safety, building strength, balance, coordination, and symmetry.