Why pay more when this accurate and versatile timer does far more for far less? You can measure the time interval between two photogates, measure the time it takes to pass through one photogate, measure acceleration of a released ball, determine the acceleration due to gravity (with a picket fence), determine elastic and inelastic collision times, calculate cycles, determine the frequency of a rotating object, determine the period of a pendulum, and count time with great accuracy. Up to 20 data points can be stored in memory for instant recall, allowing you to watch the experiment as it happens and perform calculations after the fact. Includes a magnetic ball drop. Rechargeable. May be used with or without the adapter.