A multi-purpose instrument which is invaluable in the physics laboratory, combining the functions of a multi-purpose timer, a ratemeter and a frequency meter in one compact and economical unit. Uses in the timer mode range from a simple stopwatch to more sophisticated applications such as dynamics experiments with air tracks etc. The scaler and ratemeter modes allow numerous radioactivity experiments to be undertaken, for example, variations in background radiation, half-life determination and investigation of absorption coefficients. When used as a frequency meter theinstrument will accept diversified waveforms and may be used, for example, to determine the rotational frequency of a stroboscope disc and for displaying the frequency of a waveform from a signal generator. It has four, 7-segment LED digits, 13mm high. The high brightness and large size display make it ideal for classroom demonstrations. 3 year warranty