The Xvest TurboBells™ are the fastest, easiest and most versatile dumbbell in the market. The weights can easily adjusted with just a flip of a switch. No switching blocks, no complicated dials... just toggle the switch.The Xvest TurboBells™ pair of adjustable dumbbells range in weight from 5 to 60 pounds. You can make 2.5 pound changes in resistance that allow you to keep your program going and break through training plateaus. Each dumbbell is made from high-impact ABS and high strength steel weight plates. Change weight at the flip of a switch. Simply "engage" or "disengage" a lever that selects the desired weight. These dumbbells feature an innovative "hammer handle" design that is flat on both sides. The grip is made from rubber and is designed for maximum grip and maximum comfort. The "hammer handle" keeps the dumbbell from rolling in your hand causing you to lose your grip during reps.