Scott 483 Schermack Type III Pair - Rag Remnant Blocks Print on Left Stamp EFO

Unprinted area on left stamp of a horizontal pair of Scott 483 with Schermack Type III vending machine perforations.  

The print was likely blocked by rag fibers between the plate and paper at the time of impression.  The stamps are unused, with original gum and previously hinged, with the slot perfs clear of the stamp designs.  

Very unusual to find a freak printing on a Schermack coil.