5310-01-657-2053 (23NJ45)
NSN 5310-01-657-2053 (NIIN 01-657-2053) is a lock washer in Federal Supply Class 5310, Nuts And Washers — a washer, usually round, with a centrally-located hole. Manufacturer part number 23NJ45 (W.W. Grainger, Inc., CAGE 25795).
NIIN assigned August 2016; DEMIL A (none required); ESD/EMI-sensitive; unit of issue EA (each), $0.01 gov standard price.