I’d mention this to you. I have one of those harbor freight table top rigs. It does 2,6 amp.

It was like $25

Been reliable for 4-5 years now and it get used almost once a week on our junk. We have too many things that sit for 2 weeks without being loved on.

If you don’t need a jump boost ASAP, I’ve just used that little charger for a couple hours. Stuff like mowers, wheelers and cars are GTG with 6 amps, during a lunch break.

If it’s not something completely dead.

Big ol schoolbus batteries and bulldozers might be out of my league of help to you with this baby charger.
Unless you wanna go 2 amps all night.