DESIGN & FEATURES: Includes one adjustable dumbbell and one docking tray Quickly switch weights between exercises during circuit workouts lower the downtime between exercises Easily switch heavyweights for squats and lunges to lighter weights for curls and triceps extensions Unique dial system combines 5 sets of weights into 1 Eliminate the need for multiple dumbbell sets and cut back on the clutter of your home gym with dumbbells