This VICTOR marked insulator is one that has eluded me on most of my hunts in New York where they were used.(till two weeks ago)! This insulator was designed to repalce the failed M-3890 by by the Niagara Lockeport and Ontario Power Co around 1908. The design was much shorter and had fairly short skirts compared to the M-3890. These were threaded to a lead head rather then being cemented to the pin which helped protect the insulator from heat damage when the line flashed over. Wile these insulators proved much more reliable then the 3890 when new, they may have been a failure in the long run because the top skirt cement joint was very thick and tended to expand cracking the top skirt. These insulators remain very rare in collector hands with less then 1/2 dozen examples known all of which are repaired. because of there pretty green and blue colors, they are sought after by both early multipart collectors and collectors of colored porcelain . I wish I could find 20 of them! About a dozen brown ones of these are also known of which only one is unbroken and near mint most of which were found in a substation near Durango, Colorado.[id=124474990] these were used as part of an air break switch. the big crown top and large deep grooves lended themselves to being adapted to switch and substation applications. the brown ones seem to be of a slightly later production with thicker skirts and more rounded crown I'd say the brown ones date from around 1912-1915 wile the gray ones are 1907-1910