Discovered that my SAE 5 hose ends fit the new 5/16" A1 series 368 perfectly.
Low Permeation Marine Fuel Hose - Series No. 368 | Teleflex Marine
So dont throw out hose ends, you might be able to reuse them. New ones are pricey.
The ferule part is reverse threaded and screws on to the hose outer jacket. The inner sleeve is forward fine thread and screws into the ferule locking the hose together with the fitting.
This is 5/16 hose with a number 5 fitting. The newer A1 hose is slimmer and now fits. I have some older A1 5/16 which is much thicker and wont fit. That thicker hose also does not have the Low permeation inner plastic barrier.
These were originally on some ancient Aeroquip hose which was beginning to rot
. Aeroquip 2651-05 MP 1069 hose is very expensive over $4 per foot.
They have a picture here showing a size 6 fitting, which might fit the 3/8 series 368 hose.
I personally like these fittings better than hose clamps and hose barbs.