Originally Posted by LKASurfing
The Fly High bags are in fact a 1" threaded hole in the bag. The larger fitting are 1" 1/8. That is what come plumbed in now on several manufactures for their PnP with a 1" hose.
"This fitting is a reducer from 1 1/8" female (the proprietary thread on the Attwood T1200 pump) to 3/4" male, and can be used to connect the pump direct to the port on Fly High Pro X Series ballast bags, or to any other female 3/4" connection."
Based on the above statement, you can infer that 3/4" is the size of the Fly High bag port, since the fitting to attach a pump to the bag is stated as a reducer TO 3/4".
I am unable to find the specs anywhere else, since Fly High likes to keep it quiet. If you can prove it to me some other way, I'm all ears. I'd rather have the correct information.