Correction: This is a tan Fred Locke porcelain insulator, U-955. It has the 4-1 incused markings, not the 4-2 markings on one side of the outer shell and on the opposite side of the outer shell, an incused date "JANY 2. 1901"
Height is shorter than the U-955... 3 and 1/4 inches instead of 4 inches
Thanks goes to Robin Harrison for the correct identification.
Insulator has changed ownership.