Quick MAC socket ID question

[Fyrme]

I've searched all over the internet and can't find this seemingly easy answer.

What is the difference between say a X617MM and a X617MMR, or say a X226 vs. X226R?

Beside the obvious for all you smart asses out there

 

[Gerard]

After comparing a handful of pictures, it seems to me like the "R" sockets are just newer and feature off-corner engagement. The R might stand for "revised" or something similar.

 

[gdocktor3]

Yea I'd have to agree with Gerard, exept I think R stands for "redesigned".

 

[scissorman]

Looking at both part numbers I would say the X617MMR the R would stand for radius. The corners of the X617MMR are radiused whereas the non R are not.

 

[Fyrme]

Scissorman, that one made me get off my **** and go look. First I looked at my metrics, and the only non-R I have is a 10mm that I bought because I couldn't find a 'R' version. It has the same radius corners as the mmR's. Then I looked at my sae set, which I bought mixed already, and that seems to be a valid argument, as the non-R has sharp points where the 'R's are radiused. So, I'm leaning more toward Gerard and gdoc, meaning revised, or redesigned.......However, I am more than convinced that it stands for "RARE" since I can never seem to find the mmR's for sale!