size is easy to carry. Simple and easy operation. This product is mainly used for object acceleration and measurement. Individual users can be used to measure the design speed of all kinds of playthings. Handheld type speed measuring instrument, with high accuracy measurement, 160 groups datas will be recording. Measuring speed range: 1-999m/s. Metal and fully closed, this speed measuring instrument will not affect by the and current. High accuracy, with measurement data. Humanized design unit conversion ., Weight: 0.37368353409 Pounds, Manufacturer: Jewecutger