4 holes equally spaced on 3.440 bcd; each is .397
A nut, circular in shape, which may have wrenching facilities such as flats, holes, protrusions, slots or splines in or on the periphery or in the face opposite the bearing surface. For items having a thickness (or height) exceeding two times the outside diameter, use post, electrical-mechanical equipment. See also nut (1), plain, knurled. (when height or thickness and/or outside diameter is designated as a tolerance dimension, the maximum dimension will be used to determine compliance.)
NSN 6220-01-370-4215
NSN 5950-01-153-2650
NSN 5999-01-137-4971
NSN 5950-01-305-7544
NSN 5985-01-175-3217
NSN 6150-01-356-1786
NSN 5990-01-328-9846
NSN 5895-00-076-2200
NSN 5999-01-244-8649
NSN 5945-01-046-6319
NSN 5855-00-797-8217
NSN 5996-00-740-8315