Review on ⚾ Hitting Knob: Enhance Power and Bat Speed with this Baseball & Softball Swing Training Bat Weight - Little League, High School, and Professional Practice Equipment by Steve Guillen

I think this product gets unfair negative reviews. That worked great for us. My 14 year old son plays well with the ball and often uses it in his training to increase hand speed and dribbling. The spring has a lot of power so you have to use your full body weight to push it down and hook it, but once it fires it's solid and won't move. I think some of these comments might be using it incorrectly or not strong enough. You cannot attach the spring with your hands. you have to rely on that. Here in the listing there is a photo showing how to do it as well as instructions printed on the box. Hope that helps. I highly recommend this product.