A nut having 6 flat sides and an integral washer which extends beyond the flats or periphery.
NSN 6220-00-553-8938
NSN 5996-01-451-3591
NSN 4140-01-037-4924
NSN 6105-01-032-7181
NSN 5950-01-458-5090
NSN 5960-00-851-0672
NSN 5975-01-080-0023
NSN 5915-00-061-6675
NSN 6130-00-022-4160
NSN 6610-00-935-7131
NSN 5999-01-431-8007
NSN 5915-01-351-8037