I got three scanners from a private party and he does not know the power supply. How do I match these scanners with a bucket of power adapters.

On the back of the Umax it says 12V does that mean that I look for a PS with the Output as 12V or +12V or what.

I did find one that says Output +12V--1.25A
Could this be the adapter for one of these scanners?
Do flatbed scanners have similar voltage? I have an HP, Umax and an EasyPhoto ImageWave. They are all older flatbed scanners like 1998 or so.