This is a very nice, clean, 1-2" outside micrometer with .001 graduations. It is marked "BROWN & SHARPE MFG. CO. PROVIDENCE R.I. U.S.A. NO. 38 PAT. 1,629,406". The patent number reflects a date of 1928. The fractional equivalents are also marked neatly on both side of the frame. As you can see in the pictures there is no rust, and no past owner's marks, very little minor wear noted. This micrometer features the .001" graduation scale, and from 1-2" capacity. The calibration checks out very acurate. A true antique machinist tool, and still in really nice shape!