This speed measurement instrument is mainly used for object acceleration and velocity measurement, individual users can be used to measure the design speed of all kinds of shoot playthings. High accuracy, with accurate measurement data, simple and easy operation. Large LCD display with backlit, you can see the data in the weak light environment clearly. Totally 2 versions available, you can choose according to your demands. Wifi version: with Wifi function; support record 120 groups of data, shutdown will not reset, support manual reset; default traditional Chinese, and support switch to English. Specifications: Name: Speed Measuring Instrument Material: aluminum Battery: 1 * 3.7V, 400mAh lithium battery (included) Version: common version, Wifi version (optional) Shoot speed: 0-3600s/min (0-60s/s) Initial velocity: 2-1500m/s (10-5000ft/s) Kinesthetic energies: 0-999J Shoot ranges: 0-999m Accuracy: error0.5% Host size: 44 * 73 * 33mm / 1.73 * 2.87 * 1.30in Package size: 130 * 80 * 90mm / 5.12 * 3.15 * 3.54in Package weight: 180g / 6.35ounce Packing List: 1 * Speed Measuring Instrument Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Sold by-YJL official store