Have read a lot of other negative comments. I'm sure mine went down for the count due to battery. Read directions carefully, yes, one does really have to keep it charged ALL the time, my mistake.
Recommend this product?
If Sears wants $118 for a replacement battery, that's highway robbery. Just google "battery AGM lead acid 12V 22Ah" and you'll see a ton of motorcycle/scooter/UPS, etc batteries all fitting the bill. But, since I can't get my hands on a cut sheet for the Diehard, can't verify exact dimensions. But, all the pictures I googled looked identical to the one inside the Diehard Portable Power 1150 I just pulled out.