About 2-1/2 years ago I bought a Midas Pro1 and a Furman UPS. It has worked fine. They tell you to change the batteries every 2 years. Do what they tell you. I let mine go a few months past that and on my last job it wouldn't fire up. On the unit, there is a sticker telling you not to try and change the battery yourself and to call for factory service. I called their tech support. The tech I talked to said I could change the battery and told me how to get the face plate off which is easy if you know how. He told me the batteries would cost about $150.00. I checked on their website for Furman dealers and found Moyer's Electronics in Pottsvile, Pa to be the closet one to me. I called and they said they had the batteries in stock. I took the unit up and the guy at the counter and I took off the face plate. The batteries look like the type you would find in older emergency lights. The replacement was quick. The charge for 2 batteries plus some fuses I needed for other things came to $67.00. If you need a UPS, this one is well built and have had no issues other than replacing the batteries.