Bought this to mount a Mr. Heater little buddy that mounts on a one pound bottle. The top mount won't screw in, it goes about a turn and a half and stops.
I really wanted to like this, but it is defective.
I will try to get a replacement and will update this post if, and when, that happens.
Edit: Received a replacement, I can now put an appliance on the top port, see pics.
I still only gave 4 stars necause the threads still bind. It takes some effort to get the appliance on. Also, it has very tight quarters to put the unit on a 20 lb tank. The wing bolts have difficulty going pass the plastic collar that screws onto the tank. It can be done, but is difficult.
All in all, it does what it is supposed to do but 4 stars for being difficult to get it to do so.
Also, if you can't get an appliance onto the top port after a turn and a half just stop. Get a replacement, otherwise you'll damage your appliance.