Washer is 12 mm for the oil pan drain plug
No other part numbers with same form, fit, and function found.
NSN 6650-01-435-1168
NSN 5998-01-362-3236
NSN 6145-01-444-1668
NSN 5920-00-331-0583
NSN 5905-01-501-5210
NSN 5905-00-207-3946
NSN 6685-00-997-2719
NSN 5920-01-040-3383
NSN 5965-01-572-2937
NSN 6320-01-516-3836
NSN 6145-00-883-7420
NSN 5998-00-855-4646