A cylindrical item having an internally flanged diameter designed to retain a lens or window in the objective end, or a diopter scale at the viewing end of an optical instrument. It may have one or more of the following characteristics: internal thread or machined for a press fit, method of securing, and/or knurled periphery. For externally threaded items, see retainer, optical element. Excludes cell, optical element; nut, plain knurled; nut, plain round; and ring, retaining.
Classification: Military equipments not identified by kind
NSN 6220-01-496-2032
NSN 5996-00-073-6999
NSN 5975-00-203-6020
NSN 5998-00-936-7002
NSN 5990-00-781-2575
NSN 5855-01-034-3845
NSN 6240-01-633-9357
NSN 6240-01-470-7706
NSN 7035-01-284-3535
NSN 6145-01-367-1404
NSN 5915-01-053-0900
NSN 7035-01-227-2546