Pittsburg porcelain signals
U-243
Incised on
dome JUN 10
A.M.
similar to a U-293
Hard to make out here but
incised on dome and reads
AUG 21 PAID
U-344A MLOD
Incised on
dome "FEB 01"
Hard to make out in pic but
incuse marking on dome
reads "MAY # # P. M."
U-243
 The Pittsburg High Voltage Insulator Co. located in Deary,
Pa, began prodution in 1908 and seems to have ended
sometime in 1921-1922.