6660-00-343-6391 (N657SH4PC170)
6660-00-343-6391 is equivalent to manufacture part number 2W11859. It is a retaining ring and is classified under Federal Supply Class 6660 (6660 - Meteorological Instruments), stocked for defense, aerospace, MRO, and industrial maintenance applications. This item is cataloged in the NATO supply system under 6660 - Meteorological Instruments and is available through NSN-PARTS for U.S. government MRO, and commercial procurement.