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 5975-01-407-2289
NSN 5920-00-400-6227
NSN 5910-01-566-3296
NSN 6645-01-525-7493
NSN 5935-01-215-1422
NSN 4140-00-401-7851
NSN 5910-01-596-6525
NSN 6220-01-104-7280
NSN 6610-01-420-1739
NSN 5935-01-100-1171
NSN 6645-01-463-2198
NSN 5965-01-504-5567