Hi Gary,
Mostly half inch. The plates behind the loop mounts are half inch, the tube is 7/16, grade 8 hardware very heavy.
I use the bull bar for recovery tasks and arborists activities.
I don't have any pictures of the bull bar build on my phone. New phone. I have built four of them for people here in the area will zero failures. It was fun to build too.
Jon 1985 6.9l diesel chassis running a (1979 7.5I 460), f250, 4x4, t19, BW1345, front: (Heavy duty) dana 44 ifs (Spartan lunchbox locker, drain plug and D50 Half shaft) and rear: dana 70U (Detroit Soft Locker) full floater.
3G alternator, duraspark II