About D'Addario Accessories PW-CT-9V DC Power Adapter
The adaptor converts AC wall power to 9-volt DC for powering most instrument pedals. The tip negative, the sleeve-positive power supply can handle 500mA to fuel even your most power-hungry devices. The adapter converts AC wall power to 9-Volt DC for powering most instrument pedals and other 9-volt battery devices. The D'Addario adapter can also be used to power tip-negative keyboards.