SUPERIOR ACCURACY: Uses Doppler Radar and precise algorithms to show your SWING SPEED, BALL SPEED, CARRY DISTANCE, TOTAL DISTANCE and SMASH FACTOR for each club. Can also use with Tennis, Soccer and Baseball. EASY TO USE: Turn it on, put it down and hit. Powered by (included) batteries. No wifi, no downloads, no apps needed. Captures nearly 100% of shots without "fiddling" with placement like with others. instruction manual included. LCD screen: Display measurement results and history. Camera screw: used to attach the device to tripods and other fixings. Batteries - 4x AAA size alkaline batteries Flight distance display switch button: switches between Carry and Total flight distance display modes. Scroll button: used to scroll through measurement histories and device setting