Great for baseball and softball training! Pro instructor, Mike Epstein says, "it's the best muscle memory tool I've used". Designed to help isolate the sweet spot, increase bat speed through underloading and strenghten "fast twitch" muscle fibers. Reinforced fiberglass simulates the weight distribution of a real bat without the fatigue, so you can get more swings. The concave-foam sweet spot gives instant feedback on whether you hit the ball correctly and can be moved to match your newest bat. Ridged grip tape allows you to isolate the bat in your fingers, promoting the correct grip for maximum speed. For the best practice, use golf sized poly balls. Measures 30" long and weighs 12 oz. Recommended for ages 6 - 12. Includes instructional video & 4 golf ball sized poly balls. Please note that this bat is for use with soft foam and wiffle type poly balls only.