This is the type of multipart originally used on the first section of the Winona Lake interurban in northeastern Indiana Constructed in 1907. The line used M-2470's produced by New Lexington some of which were marked on the sides of the crown THE OHIO BRASS CO/ MANSFIELD OHIO . I believe only a handful of these marked and unmarked have surfaced . Two surfaced on eBay a few years ago and a few more may be floating around ... These insulators were changed out in the early 1920's with small three part Thomas units and later with JD uniparts and other random two part multi's [id=468080146] A detailed explanation of why New Lexington marked insulators with Ohio Brass markings can be found in the new Unipart porcelain guidebook by Elton Gish