SoulBay Universal Power Supply AC to DC 3V 4.5V 5V 6V 7.5V 9V 12V Multi Voltage Power Adapter with 8 Plugs for Center Negative(-) Tip Negative Effects Pedals Keyboards Instrument - 2A Max;

Description:

This is a universal power supply for all your pedals, effects, wireless receivers and more.
Features include worldwide input, regulated output in multiple voltages, six adapter plugs and more.
This adaptor is designed to supply power where and when you need it. With selectable DC output up to 12 volts and plugs to fit most small electronic devices, it replaces a box full of batteries.
It gives a universal regulated switching mode supply with selectable AC Input 100 to 240V AC (so with an electrical plug adapter it will work anywhere in the world).
It has selectable DC Outputs: 3v/ 4.5v /5v /6v /7.5v /9v /12V. The charger also includes 6 detachable DC output plugs, so that it will fit almost all DC input sockets. Used for printers, games consoles and many other appliances.

6 Connection Tips Spec.

2.5*0.7mm, 3.0*1.1mm, 3.5*1.35mm, 4.0*1.7mm, 5.0*2.1mm, 5.5*2.5mm
DC Plug Polarity: inner Negative(-), outer Positive(+). Polarity is irreversible !!!

Compatible with:

Electronic/Talking Dartboard, Router, Guitar, Pedal, Effect, Piano, Keyboard, Baby Monitor, Scanner, Drum Metronome Trainer, and other device.
Please check carefully for the Voltage and the Connector specs before bidding. Thank you.

Package:
power adapter 30W [Negative Version]
6 DC Tips

How Can we distinguish the Correct Polarity?

You can easily recognize Polarity by looking at the symbol near the DC power input of your device. It's that barbell looking thing with a + and - on opposite ends.
If the center "c" shape opens to the -, it's negative polarity! (the + is on the outside and the - is on the inside), buy this adapter. If it's the reverse of that, buy one with the correct polarity.