SKLZ Sport Radar will measure the velocity of just about any ball or puck you can throw, shoot, kick or hit. It keeps track of top speed, per session and all-time, between 15 and 150 mph in either mph or km/h. It is the same technology that professionals use, so you know it's accurate. Its large LED display makes numbers easy to read. This baseball speed detector stands on its own, so there is no need to hold anything. Just set it up on the ground or bench, behind goals, nets and rebounders. With its durable, portable casing, you can use it indoors and outdoors. It runs on four C batteries (not included). SKLZ radar is an ideal training tool for baseball, softball, soccer, football, tennis, lacrosse and hockey.