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 6610-01-303-4272
NSN 6320-00-823-2015
NSN 4140-01-155-8363
NSN 5895-01-497-1022
NSN 6320-00-468-5015
NSN 6645-01-585-2264
NSN 6110-00-891-9917
NSN 6620-00-350-4594
NSN 6320-01-512-2031
NSN 5835-01-352-7211
NSN 5999-01-225-8653
NSN 5996-01-448-6814