Features: Use of high-speed single chip microcomputer to do- voltage sampling test, and drive the LED lamps display voltage, realize the integration of board and card, reduce the defect rate. 0-300V adaptive- voltage, suitable for most series and parallel- bead test. When testing, the use of gradual- starting modes, voltage automatically adapt, current gradually increase, never burn lamps beads. Digital display real-time voltage output, with adjustable voltage, voltage value can be corrected by itself. The digital meter uses green luminescence tube, the display of 00- is short circuit, the display of 300V- is open circuit. Each group of LED strip of the same LCD- TV display voltage should be the same. Hot and cold isolation, never electric shock. Power cord and box integrated design, easy to carry out. You can light up the LCD- TV screen without dismantling the screen. Specifications: Material: Plastic Input: 85-265V Output: 0-300V Power: 18W Size: Approx. 180x105x40mm/7.09x4.13x1.57in Color: Black/Red Type: AU-/US/UK/EU- Package Includes: 1x Lamps Bead Tester note: When you are unsure of the positive and negative electrodes, use 19V voltage to detect the positive and negative electrodes. Do not use 300V- voltage to detect derectly. The 300V- voltage may cause damage to the device. During the test, do not look directly at the lamps bead due to the highlighted version. So as not to hurt the eyes.