The Everlast Hyperflex Strike Bag is ideal for athletes looking for intense training outside of the gym. Design allows for easy movement around target, increasing cardio, leg conditioning and hand-eye coordination. Dual hyperflex individual locking springs provides three workout settings for comprehensive punching, reflex and cardio workouts. Speed flex setting (Lock Base, Unlock Neck) is ideal for fast punches, combinations and reflexes. Straight flex setting (Unlock Base, Lock Neck) is ideal for punch techniques, agility, footwork, defense and timing. Hyperflex setting (Unlock Base, Unlock Neck) is ideal for ultimate accuracy, speed, and agility training, and simulates sparring sessions for striking and defense. High density plastic base approximately 70 lbs when filled with water; 63" in height at highest setting.