Starrett No. 120 Inside Micrometer Set A
This is a nice clean early inside micrometer set with a capacity of 2-8" by using interchangeable rods. The interesting note about this old design is that the rods where inserted into the micrometer head, then the scribe lines on the head and rod have to be aligned for the various lengths desired. The No. 120 model was discontinued in the 1930's and the new No. 124 was offered after that. The No. 124 model was different, perhaps better, because although it's design was about the same the new rod design featured a solid stop, and rods for each 1" increment offered, where this one has a line to be matched up in the head every 1/2" on the rod. The head has .5" travel. The head is marked "THE L.S. STARRETT CO. ATHOL MASS. U.S.A. and is still in very good condition, with very minor darkening of the steel in a few place, and good snug movement, like a top quality new micrometer has. The case is leather covered wood, hinged, and a front clasp. The top of the case has the Starrett name in the center. The outside has some corner and edge wear noted, but overall in good working order. The inside is felt lined with cut outs for the rods. A rarely seen old machinist tool, by a top, well known maker!