After drilling many seized/broken down pipe studs out of exhaust manifolds for friends, I went looking for a solution. There really isn't any good ones that I could find so I made some and after a few changes, came up with a 10 X 1.5 mm 360 flanged brass nut that that is 19mm long and have a 14mm hex. The 360 brass will not seize to the stud and the longer length covers all of the threads and makes them really easy to access for removal. The down pipe nut is the only 14mm hex that is 1.5mm thread so if you use a nut for the manifold on the down pipe stud it will cause you some problems. JIS (Japanese Industry Standard) 14mm hex is always 10 X 1.25 mm. Nice to know when you have to pull a trans at the track that these nuts will come of, and easily too. No chance of mixing them up either.