6660-00-561-4747 (SMC294070)
6660-00-561-4747 is equivalent to manufacture part number S516897. It is a observation window 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.