U-293A: USA

3 1/4" X 3 1/2" (82mm X 88mm)

 

(dome incuse) PP

{Porcelain Products}

 

Picture courtesy Bob Berry

3 1/8" X 3 3/8" (79mm X 85mm)

 

(skirt incuse) B & O

 

 

Picture courtesy Bob Berry

U number assignment by Jack Tod.

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