I had a 3" river country 2.5" stem thermometer and like others mentioned the thermometer was off in some instances (maverick running through weber grommet used to compare temps) - but not always. Additionally I had built an ash catcher for my coal basket that had to be wrestled out with the thermometer in place. So to solve this in my stainless uds I bought a stainless reducer with a female 1/2" NPT thread which matches the river country as well as a new Tel Tru 3" dial with a 4" stem. So the bushing and nut stays installed at all times and the thermometer can be easily removed without any tools in a matter of seconds. I used similar although larger reducers for my intakes but they can be secured much better than the closed pipe nipples that I used on my first builds.
[ame="http://www.amazon.com/gp/product/B003H05EQU/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1"]Stainless Steel 316 Cast Pipe Fitting, Hex Bushing, MSS SP-114, 3/4" X 1/2" NPT Male X Female: Industrial Pipe Fittings: Amazon.com: Industrial & Scientific@@AMEPARAM@@http://ecx.images-amazon.com/images/I/51JE-ydSplL.@@AMEPARAM@@51JE-ydSplL[/ame]
[ame="http://www.amazon.com/gp/product/B003GXF6RA/ref=oh_aui_detailpage_o02_s01?ie=UTF8&psc=1"]Stainless Steel 316 Cast Pipe Fitting, Hex Locknut, MSS SP-114, 3/4" NPT Female: Industrial Pipe Fittings: Amazon.com: Industrial & Scientific@@AMEPARAM@@http://ecx.images-amazon.com/images/I/51hfPlhY4AL.@@AMEPARAM@@51hfPlhY4AL[/ame]
[ame="http://www.amazon.com/gp/product/B001L4IISK/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1"]Amazon.com: Tel-Tru BQ300 Barbecue Thermometer, 3 inch black dial with zones, 4 inch stem, 100/500 degrees F: Kitchen & Dining@@AMEPARAM@@http://ecx.images-amazon.com/images/I/51pTM5TgLtL.@@AMEPARAM@@51pTM5TgLtL[/ame]