Measure it from one side of the 13" markjmc said:i used a tape measure. pulling against the tab it measures right at 7/16"...pushing against the tab it measures 1/2"...if that makes sense. your comment that you weren't aware of 3/8" anchor bolts is very helpful though.
About a 24% reduction in cross section of the boltMule said:What's a 1/16 of an inch among friends? Hey.. close enough for government work... Always hated that saying!