ALLOSUN EA103 Signal Pick Up Need to be used with Automotive meter or oscillograph. Please Note: the Pick up set is designed for general application. It only works with signal input function digital multimeter It can be used in the adjustment and diagnosis of Automotive engine Position the signal Pick up as far away from the distributor and the exhaust manifold as possible The distance between the spark plug and the clamp of the instrument must be less than 10cm during test, and the ignition frequency of the engine ignition system must be between 10Hz and 400Hz Because different engines may have different ignition systems, the instrument's test range of engine rotation speed may vary with different engines This instrument is designed to be used with automotive meter or oscillograph. It can be used in the adjustment and diagnosis of automotive engine. Using this instrument and an automotive meter, you can accurately measure some parameters of engine system. It is very easy to use. Operating temperature: 0 to 60 Relative humidity &lt; 80% Dimensions: 98 x 35 x 20 mm (for main body only) Weight: about 105g