Bolts on Remington M1903A3 rifles have a parkerized finish and are stamped with the letter R at the root of the handle; while Smith Corona bolts are blued and usually stamped with a letter X on top of the handle, although some are unmarked. Some extractors on Smith Corona rifles are stamped with a letter S on the bottom. Stamped steel stock fittings were generally blued, although some were parkerized in late production. Butt plates of the Smith Corona rifles were checkered with 10 or 11 lines per inch, while Remington used 16 lines per inch.