12-09-2012, 02:41 PM
That is basically a Lufkin micrometer. Pratt & Whitney bought out the precision measurement division of Lufkin in November, 1966, pretty much just changed the name on the tools and continued to sell them. Here is a shot out of the Lufkin #9 catalog showing that mic with the Lufkin name. I don't have any Pratt & Whitney mics, but I do have a few 6" rules, which are very nice.
Tom
Tom