Square cross section just like OEAm
Superior SA21477 Packing, Cylinder Base
Good O-Ring, same as the original on my IO-540-D4A5. If youre looking for the oil dipstick tube o-ring that goes under the yellow cap, with a flip style top, this is the one.
This O-ring was absolutely awesome!
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The o-ring is a -08, but Superior lists it as a -8 on their web and packing slips. We stock MS29512-08 as well. This is the Superior version of the same o-ring.