What power supply do I need for a FreeAgent Seagate External harddrive?

[uOpt]

I have a Seagate ST302504FDA1E1-RK FreeAgent Desktop 250 GB USB External Hard Drive and we misplaced the power supply.

There are no markings on the unit and the downloadable manual doesn't say it either:

What voltage, amerpe and polarity do I need for that?

Thanks

 

[uOpt]

Found it, in case anyone has the same problem and finds this thread:

12 V AC, 2.0 Ampere, plus is inner.

 

[jackschmittusa]

"plus is inner" is commonly referred to as center positive or just c pos.