| PP |
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| U 293B's |
| U 283's |
| Porcelain Products Inc. was formed in 1927 from the merger of several other manufacturers, marked their insulators with an incuse "PP" inside a rectangle, ink stamped date marks start circa 1950 and run through 1958. |
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| U# ??? (possibly deformed U 293B's, same general shape but considerably taller. |
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| Characteristics: Color(s) --- white, green, cobalt, yellow, dark brown, dark mottled red brown, chocoltae brown Pinhole(s) --- glazed Pinhole Top(s) --- dime sized dome, plain, slight dome Fire Rested --- petticoat Wet/Dry Processed --- wet Marking(s) --- incised on dome "PP" inside rectangle |
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| Incised on dome "PP" in rectangle |
| Incised on dome "PP" in rectangle |
| Incised on dome "PP" in rectangle |