I have no idea what it is. There are five openings which is a little unusual. The hose connections makes me think water was the coolant, but that is only a guess. I cannot see the path, but it looks as though the center barb inlets to nearly three lengths. This is what I am thinking. It is designed to first cool a hot effluent gas. This is the purpose of the long path. I can see it exits at what looks like a cold finger. I'm guessing a cold finger is inserted and condenses the gas there. I'm guessing a septum is there to extract the sample. However, I've never seen anything like this before.