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 5895-00-205-2924
NSN 6135-00-284-1406
NSN 6645-01-500-0827
NSN 5905-00-785-3359
NSN 5855-01-235-5491
NSN 5855-01-456-8667
NSN 7035-01-012-2259
NSN 4140-00-451-8374
NSN 2925-00-986-2055
NSN 5915-00-216-5909
NSN 6645-01-206-4888
NSN 6645-00-140-5173