Lighter plug mate. It's OK, I bought it when I was off-roading, handy to have when you're doing running repairs in crap conditions

. I've used it for some pretty stubborn stuff and it's never failed me, but it's no-where near as effective as an air powered one or the very expensive 18V ones. I'm pretty lazy these days and it's much less effort than undoing wheel bolts by hand
Was only about £15 IIRC but can't remember where I got it from. I've seen them in Aldi and the like.