We have this training device in the garage laying on a turfed surface. We watched the you tube training video and followed the instructions. My daughter was having trouble getting the mechanism to "click click." She then really started to focus her attention on her push and drive, and there it was. We moved the spring to 2, and she was click click 4 out 5 times. She pitched maybe 50 balls, and turned and said, "this is a workout."
This thing is great. It really is. I have been coaching a long time and have really been trying to emphasize the push off of the rubber while fast pitch pitching. This training device gives you immediate feedback if you are pushing off like you should be.
And, Coach Kane was wonderful to work with via email. I asked several questions about this device, and he was prompt and on point with his answers. I highly recommend buying this if you are a fast pitch pitcher and want to throw harder.