Norm, I suspect that Wheeler may produce many of the brand name magnetic tip bits. I have one of their 89 piece sets. The only thing about the set that I do not like are the supplied Qty(2) handles - too long to control. I've ordered different style handles yesterday from Brownell's. The Wheeler bits measure 0.25 across the bit flats (hex),i.e., this is also the same hex size for the Brownell Mag-Tip driver handles.