18 inch diameter; raised hole in center
No other part numbers with same form, fit, and function found.
NSN 5965-00-863-6031
NSN 4140-01-526-6874
NSN 6685-01-553-1974
NSN 5950-01-290-3967
NSN 5935-01-137-3846
NSN 5998-01-216-0997
NSN 6110-00-271-9928
NSN 5930-00-294-9189
NSN 6685-00-797-7543
NSN 6105-01-421-2644
NSN 5905-01-068-3631
NSN 6150-00-495-6008