If you are just looking to protect against a few second power loss you don't need too large of a ups. If you want something that will keep you going during a blackout, thats a different story. Micro Center has a good selection of inexpensive ones.
Most people do not get a battery backup and only put their computer on it. Most when they get it, will plug their Desktop or laptop, Modem and router, and monitor if it's a desktop. So, you must factor all of these in. I personal reccamend APC, for they are quite resilient. However, it will also depend on your budget.
Get a good name brand. Not very cheap ones. Microcenter has a good selection.
It's called a UPS, Uninterruptible Power Supply. Not UPS as in the mailing company lolz. This microcenter has it near the hobby area and the cd/dvd area. I'd recommend going for the cyberpower 1350 UPS since they have been making revisions of these babies for years.
I would get a something they microcenter recommended but get somthing good 1000 Watts
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