Looks at the specs for it. As long as its the exact same voltage and at least the same (can be higher) amperage, it’ll work. 

Yes but some AC adapters have the the +/- reversed from the typical. Just looking for reassurance so I don’t damage the T25.

I don’t have the T25 but I have used a ton of routers/modems and the standard polarity has been the same on the ones I have for my region. You can always check it with a multimeter. 

If you’re in different regions, I wouldn’t trust it as much

For more information on the usage of power adaptor for sb8200 and T25 please check the link below : 

http://arris.force.com/consumers/articles/General_FAQs/Input-Voltage-Amperage-and-Connection-Type-for-Broadband-Products