I have four APC brand uninterruptible power supplies. These are the older design that have real copper transformers as opposed to newer PWM versions. These are all capable of line-interactive operation through the transformer, so they don't use battery power for minor grid fluctuations.
Runtime is of course dependent on load and age of batteries. I don't know if these are pure sine wave or modified. They work fine with every load I've used. Each unit has a ~6-foot permanently attached grounded power cord. 120V/60Hz.
Used condition, but of course fully functional. Batteries not included. Selling because I don't need them anymore and I don't want to buy batteries for them. Pickup at Mukilteo Taco Bell by appointment only; no other travel. Cash only. Feel free to contact me if you have any questions!