5310-01-444-8669 (MB27)
NSN 5310-01-444-8669 (NIIN 01-444-8669) is a lock washer in Federal Supply Class 5310, Nuts And Washers — a washer, usually round, with a centrally-located hole. Manufacturer part number MB27 (Fag Bearings Corporation, CAGE 43991); also referenced as MP101030208 (Imi Systems Ltd).
NIIN assigned May 1997; DEMIL A (none required); unit of issue EA (each), $9.31 gov standard price.