This is a remix of slicerd's excellent Ghostbusters Leg Hose adapter. I created an insert that screws into the visible hose adapter part. This allows you to carefully cut a small hole into your flight suit and screw the hose adapter into the insert, which seems to hold the hose and adapter parts quite snug and well in place. This also prevents you from having to sew or glue the adapter onto your flight suit, which can be problematic (especially if you suck at sewing like I do).

The hose I ordered from gbfans.com and glued into the hose adapter using some J-B Weld. Be careful not to glue the hose too far in so as to avoid getting excess glue in the internal threads, thus mucking up your print.

I printed this at very fine resolution and with a LOT of infill to make it as durable as possible. Also, you'll need supports as the outside leg hose adapter has a bit of a shelf on the inside that will need it.