Right, I've got a Marshall Bluesbreaker II pedal, and I was wondering what kind of power supply I should use with it. I've looked at a Boss supply, but will that only power Boss pedals? I'm confused. Feel free to recommend any types that I should look at.
that pedal runs on a 9V battery...

most of the time there will be a printing of polarity and input voltage near the jack for the power cord.

most of the time the Boss 9V power supply will work on just about any pedal that runs on a 9V battery.

It does say run on boss pedals only but thats so you go and get more plugs and that makes then more money

if you look at this link

under Recommended Accessories:

youll see the boss plug, so yes it will work
i just went to radio shack and got a 9v adaptor. it was like 4 bucks. its a little powerful but thats adjustable.
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