a hard line to -an is a 3 piece compression fitting
tube flare nuts are 2 piece fitting and you flare the hard line,and the shank sticks out the nut.
hardline comp fitting has the red nut go on the hard line,then the copper ferrel ring,the the -an hardline adaptor
as you tighten the red nut to the fitting it will compress the line and ferrel
it was kinda hard when i did my line,I used the wood handle to tap the nut on the line then the ferrel the the adaptor taped on to start the threds
you dont whant to run it till its out of threds so it can be open and resealed on that same ferel.
