HDE PC Power Supply Tester 20/24 Pin PSU ATX SATA HD Green indicator light = power is ok.Test your power supply and avoid damage to your expensive computer equipment with this ATX power supply tester. Simply plug the tester in to your power supplys 20/24 pin female Molex connector and the LED lights will indicate how safe your supply actually is. Connects to your power supplys 20 pin Molex connector Prevent accidental damage to your computer. Green LED lights indicate status at a glance.Sturdy plastic casing - 20 and 24 pin connector. +3.3V, +5V, +VSB, -5V, -12V and +12V leads for monitoring voltage output