New guy questions

ok I have been at WM about a month now . I have a cpap the shop gave me a inverter with a 12v cigarette lighter plug. to plug in the 20v plug in the truck. it wasn't enough power for my cpap so what the shop did was where the big inverter is I can unscrew the caps by the post and use a eye to put on the post and screw the caps back on the posts. now my inverter will run 24/7 and it's easy to slip seat with.