LCD indicate the status of voltage. The power supply tester is a robust voltage tester for PC-power supplies: ATX, BTX, and ITX compliant power supplies can be tested. Simple and easy to use, no batteries are needed. Connect to the power supply's 20-pin Molex connector. Equipped with +3.3V, +5V, +VSB, -5V, -12V and +12V leads for monitoring voltage output. The item is a LCD power supply tester.It can test your power supply and avoid damage to your expensive computer equipment with this power supply tester. The device is suitable for the ambitious hobby user, as well as for a quick functional check in a specialized trade. Specification: Support 24Pin, ATX 20Pin interface Support SATA interface Support 8Pin, 4Pin interface Support PCI-E graphics 6Pin interface Support the floppy disk interface Support ATE hard disk interface Test voltage: 3.3V, -12V, 12V1, 12V2 + 5 VSB, + 5V, and PG time Size: Approx. 121 x 62 x 19mm/4.76 x 2.44 x 0.74 inch Colour:gold Material:Aluminum Alloy Operation: 1. Plug power supply 24 PIN and P4 , P6 or P8 into the corresponding jack of the power test suite. 2. Power on the supply of power, will hear "DuDu" ring , if no flicker then the power supply output voltage is normal. 3. If a certain voltage signal was not detected, or the detected voltage value over the normal, will issue a "DuDu" long buzzer ; if the corresponding voltage value or PG flicker too, then the power is failed. Package Contents: 1 * Digital LCD Power Supply Tester