Wonderful Fire King milk glass coffee mug produced for Humble Oil for its Put a Tiger in your Tank promotion for their Enco Extra and Esso Extra gasoline circa 1959 - 1970. It is in good condition with what looks like a few scratch stacking marks near the bottom, but has no nicks; chips or cracks and the decal is intact. The inside of the mug has no stain or scratch marks to these pieces, but with all glass pieces of this time period there are manufacture defects of rough mold lines and straw marks. The bottom of the mug reads Anchor Hocking Fire-King Ware Made in the U.S.A. It is a fine gasoline advertising piece that is fully functional also.