An absolute must-have for fighters who are training as well as any athlete who wants to develop excellent hand-eye coordination. This relatively small, unobtrusive unit helps increase hand speed. Bouncing up and down also helps raise fitness levels and burn calories. Hitting for just a couple of minutes each day is effective with almost no hassle. This speed bag assembly with the fight station is designed to only fit into a Gorilla Gym core doorway unit. It cannot be used without a core Gorilla Gym unit as there is no way to attach it to anything. Please contact us with any questions before you buy.