I've come to the conclusion these studs are not stainless steel...they strip very easily. And they're too short! Stacking two busbars to top balance only leaves a few threads to work with and that's only if you skip the lock washer. I have two cells now with the top few threads pulled off and I'm only using a nut driver to snug them down for top balancing. I'll be OK once they are assembled as a series string since there will only be one busbar thickness to deal with but plan to be VERY careful! I've ordered some flange nuts and will ditch the supplied hardware in hopes I can get a respectable connection.