For you guys using lines with loops on both ends, how are you attaching the line to the backing?

Thanks

tie a bimini twist in the backing and loop to loop to the fly line...

what ever loop knot you tie, make sure your loop on your backing is big so you can pass the spool of fly line through it.

^Well said.

And you'd be surprised how easily they go through the guides! I had that luck ... once.

honestly i cut the loop off an tie a nail knot an leader to fly line i use loop to loop