What is accurate to GB1 for attaching the uniform hose connector? I have looked over the pics and it seems like a thick fishing line like material. Any thoughts?
I dont know what they used in the movies but all i did was connect it using strong cotton thread & that did the job fine
It probably isn’t worth you worrying too much about using the exact type of material to hold the hose connector onto the leg. 
Just as long as you have something to stitch it to your jumpsuit leg.
I used dental floss. Really freakin’ strong.
I have one of Thiago’s hose connectors and I basically sewed each hole several times and then i used hot glue on the inside of my flightsuit to anchor the ends of the thread. I only used the regular cheap thread from Walmart