MENSI 1LB Propane Gas Bottle Refill Adapter Grill Stove Connectorwith 1/4" NPT Male Thread

I used these to make a propane fueling system for a potato cannon. 1 full 1lb bottle, controlled (open and close) by a valve, fills an empty 1lb bottle that has a pressure gauge. The empty tank acts as a "buffer" tank to help me meter the right amount of propane into my spud gun. And from that, I T'ed in 1/4 rubber hose that goes to a tire chuck. On my spud gun, I have valve stem, so once my buffer tank is to the PSI I want, I air the potato gun up As affordable as these little adapters are, I'm going to buy 2 more because I know they'll be useful one day. This adapter, and a valve, and you've got propane everywhere you need it

Worked to fix a broken regulator connection

Worked perfectly for my application

Good quality but did not fit on my mini burner.

Great quality

Perfect in every way and does exactly what I needed it to do

Works as expected

I'm not sure how this thing could be bad but I am unable to get it to seal where the propane screws in. Incorrect o-ring? It worked but I could only used for a a short time in a well-ventilated place because the propane wouldn't stop leaking. Tried adding Teflon and another o-ring I had to no avail. So yes- it tapped my propane bottle for my fire breathing pumpkin. But then I had to add a ventilator fan to keep it from turning into a pumpkin grenade and the propane bottles ran out quickly because of the leaking propane even after I close the valve I placed immediately after this fitting.