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 5996-00-525-1777
NSN 2925-00-468-5273
NSN 5960-00-848-1900
NSN 6150-01-170-5658
NSN 5996-01-074-7041
NSN 2925-00-972-8180
NSN 5930-01-192-2364
NSN 5999-00-973-6891
NSN 5950-00-566-0063
NSN 5905-00-110-5153
NSN 4140-01-407-2880
NSN 5835-01-629-2044