What I guess I mean by the 5th port is that most condensers I find, and what makes sense to me, have an input and output for the gas and another input and output for the cooling flow - 4 connections. In my photo, the 2 small connections on top are for the inner coil. The bottom left connection is for the outer tube. The connection on the right end is for the outer tube. The large 5th opening on the top of the outer tube to the right is what puzzles me. Like I said, I'm not a chemist. I assume there's some name for this coil with that 5th opening.
The outer tube is 16 inches end to end. This doesn't include the right end tube connection, which adds another 1-3/8 inches. The 2 top small coil connections and the bottom left tube connection are 5/16 inch ID and 7/16 inch OD. The right tube end connection is also 5/16 inch ID and the bevel end OD is 3/4 inch. The large mouth on the upper right side of the tube is 1-1/2 inch ID and 2 inch OD.