We carry one and try to remember to charge it monthly, which requires plugging it into the wall until the light turns green. We bought it at Costco and it was something like $85, replacing one that was about 10 years old that no longer held a decent charge. Good when you do something dumb and need a jump start. For us that is somehow having the tow car battery drain while towing it, about 2 times a year.

We carry one and keep it charged. It's been great for the air compressor, both for the truck and trailer, but also for our bicycle tires!! I think we've only used it once to jump start our vehicle. Of more importance from an income and business perspective, for us it's also our back up if we run out of battery power when we're at an art show, got to have someway to keep our phone charged up so we can accept credit cards. Nothing worse than thinking you have a sale and then no way to process their card:(

I carry one also mine has a small inverter I mostly use it for the same reasons.......back up power for phones & laptops during boondocking when Im lazy sitting outside.........LOL