• The frequency is adjustable, which can detect the fire adjustment of various working conditions • The design of the flashover detection table is enhanced, and the flashover hole is far away from the adjustable knob, which is safer to use • With 3 indicator lights, it can detect whether there is a signal coming, whether the fire is not adjusted is the problem of the instrument or the problem of the spark plug, the judgment is more accurate • It can be judged whether the spark plug is good or bad, the straight line of the spark is good, and the intermittent is a problem • The aging degree of the spark plug can be judged. It is better for the spark to be brilliant purple, and the dark red is badly aging •It can be judged that the spark plugs of different brands and different specifications, under the same signal, it is better to have a sharp flashover and a loud sound, and vice versa How To Use: • 1. Put the spark plug in test hole 1 or 2. For comparison, put the new spark plug in hole 1 and the old spark plug in hole 2. • 2. Connect the power supply. • 3. Turn the key switch 4 clockwise to turn on the tester, the indicator light 3 is on, and the tester works at 1000rpm/min. • 4. Turn the key switch 4 clockwise again to adjust the working frequency between 1000 rpm to 6000 rpm. Note: • 1. Please turn off the power before placing the spark plug. • 2. Do not touch the spark plug with your hands during work to avoid danger. • 3. The higher the frequency, the stronger the spark intensity. Package included: •1 x Spark Plug Tester •1 x Power Adapter