(L to R): Blue taper top mold; middle is an unlisted Blue Aqua taper top mold; right is an aqua square dome mold.

The taper top molds have a smaller dome and a skirt with no shoulders. The square dome molds have a larger squarish dome and a skirt with shoulders.

The taper tops were found in service in Southern California on the ATSF RR line. The aqua square dome mold type hoopskirts were found on the same ATSF RR line but in Arizona.

See next photo for view of base differences. [id=610074673]