Greetings all, I'm wondering if anyone can enlighten me on why the
external valve faces on Simplex unit pneumatics all have two little
puncture marks on them.  Did they outsource their valve gluing to
a bunch of rabid pit vipers or what?

Yes, I know, reptiles don't get rabies; it's figurative.  The little
'bite marks' are near the center of the valve facing, about 1/4" apart,
and don't effect the seating of the valve.  I'm guessing it has to do
perhaps with the machine that installed the little aluminum retainer
ring on the valve stem?

Skip Downing