Secondary metering rod oddity

[novadude]

I have some secondary rods stamped "AX" that are different than any I have seen before.  The had a dull grey appearance, and I saw what appeared to be light rust in areas.  Sure enough, they are magnetic and appear to be steel?!?   

Has anyone ever seen steel rods before?  Measuring and comparing to brass current aftermarket "AX" rods, all dimensions look the same.  They have the slot that was used on the early rods.  This is a new one for me, as I thought all factory rods were plated brass. 

[Cadman-iac]

  Hey Novadude,
 I just checked the site for new posts and saw this one.  I looked at what I've got on hand and I have 2 sets of the AX rods, but both are the brass with whatever coating is typically used on them.
 Out of curiosity I checked all my other rods with a magnet and I found a set of Ak's that are steel. Out of some 70 or so rods, that's all I've found.
  Who'da  thunk it?

[novadude]

So I'm not crazy and they do exist!  haha