CONVENIENT - It checks to the voltage on all wires to ensure that the power supply is functioning properly. Power tester fully supports ATX, BTX, ITX power. Plug the power connector into this power tester and you will know immediately if something goes wrong. ESSENTIAL - This power supply tester is an essential tool for all electronics engineers. Use the power supply tester to display the voltage data of the device under test on the device's built-in LED screen. You can accurately detect power problems and prevent damage to the motherboard. CONVENIENT - It checks to the voltage on all wires to ensure that the power supply is functioning properly. Power tester fully supports ATX, BTX, ITX power. Plug the power connector into this power tester and you will know immediately if something goes wrong. WIDELY USED - It allows you to quickly diagnose or troubleshoot power problems, which are the first things to check when diagnosing computer problems. Check the 20 / 24-pin ATX (motherboard) power supply, SATA (hard disk) power supply, Molex (old hard drive) power supply, Mini-molex (floppy disk) power supply and 6-pin PCI-e (graphics card) connector. MULTIPLE FUNCTION - Fault alarm, LED display, complete test interface, small and beautiful appearance, complete test functions, etc. Easy to use, just plug in connectors and green LED illuminate to show which pins are getting power. EASY TO USE - The operation instruction on the face of tester Connectors: Floopy,HDD,CDROM,SATA,4PIN(P4),8PIN,6PIN.Power supply will automatically turn on when connected.