Heitkemper a jeweler/retailer in Portland Oregon. This is a 16 size watch, not technically railroad grade but with 21 jewels. The watch features a 14k yellow gold filled case with hinged front and back covers, enamel dial, Arabic numerals, blued steel hands, sub seconds hand, and a 21 jewel nickel movement. It is an open face, stem wind, stem set watch (not lever set).
The movement serial number is 175424. Only 2500 of this model were made. The movement is double signed Hamilton & G. The case measures 51.5 mm in diameter, and 13.8 mm in thickness.