After a snowstorm and 4 days with out power, no heat, and declared state emergency my builder said to go to RE Michael Fredericksburg to get a regulator for my fireplace to place on my 40gallon tank. They usually are about 5" in diameter. I brought the fireplace book to be sure. He sold me ab LV 404B96 which was a foot long. When I hooked this up to my small 40gallon tank gas just poured out the top of the regulator. I am pretty sure it was not the one the manual recommended because the recommended one has no such hole on top. The one for my fireplace usually runs $20.00 where this was $100.00. With LP,it is not the time to experiment with types the manual does notrecommend.