1.[D UNIQUE DESIGN]Sharp stainless steel probe can pierce insulation and reach tight areas. Adopt the integrated structure design of the probe protection cover, needle guard function is added to ensure that there will be no stab wounds and the guard will not be lost. Convenient to carry and take it wherever you go. 2.[DIGITAL LED & BUZZER BIDIRECTIONAL INDICATION]The alligator clip and probe of voltage tester can be connected to the positive and negative poles bidirectionally. Buzzer pulse once with red light on when is positive, beep twice shows negative pole with green light. LED not backlight digital readouts on the voltage electrical tester makes the data clear & visible under any light conditions. 3.[COMPUTER SAFE, STURDY & FLEXIBLE]The professional auto circuit tester has a built-in circuit board chip, which is r and more sturdy than traditional test lights and prevents the car computer board from burning out. Spring wire can be ly stretched up to 140 inches, which ed a wide measuring area.The Anti-bending design of the tail wire ensures no need to worry about bad of the line. 4.[3-72V WIDER VOLTAGE RANGE]Compared with the auto electrical tester on the market, the maximum voltage measured is only 48-60V, but the maximum voltage that our technology can measure is upgraded to 60V. Normal digital display within the range of 3-72v, less than 3v display '---', beyond 72v display blank. Resolution to .1V voltage reading with high accuracy to ±0.2V, small error can provide more professional help.