LED 20+4-pin Power Supply Tester w/8/6/4-pin Connectors LED 20+4-pin Power Supply Tester w/8/6/4-pin Connectors General Features: Voltage tester for your PCs power supply On/Off switch ATX, BTX and ITX compliant Aluminum casing Plug in SATA connector, press on/off button and check LED light (+12V/+5V/+3.3V) Plug in HDD connector, press on/off button and check LED light (+12/+5V) Plug in (Floppy) connector, press on/off button and check LED light (+12V/+5V)