For pedals with higher power requirements, use this current doubling adapter with a 2.1mm jack to combine two Pedal Power outputs. (Frequently used to combine outputs 5 & 6 on a Pedal Power 2+ to create a single 9V 500mA output.) This adapter will accept any cable with a 2.1mm plug.
Power Supply Connector: 2.1mm Straight Barrel Plug (2)
Pedal Connector: Jack for 2.1mm Plug
Polarity: Standard (Center Negative)
Length: 4 in / 10 cm