Get to work on those digs, sets, and serves with this training tool! It releases balls at speeds up to 60 mph from a high release point of 5’6"H. The release point makes timing accurate to that of a human setter. A simple dial controls the amount of topspin or underspin that is desired, therefore the duplication of varying degrees of topspin serves can be trained with. Easily move the 48 lb trainer across the court on non-marking casters. No tools are required for assembly.