A cylindrical-shaped nut, the end opposite the bearing surface being designed with an internal socket or splines for use with an inserted wrench.
NSN 5935-01-140-5606
NSN 6220-01-086-2080
NSN 6240-01-416-7474
NSN 5855-01-286-9928
NSN 6645-00-126-0286
NSN 5945-00-881-7187
NSN 6220-00-759-8611
NSN 6620-01-078-3160
NSN 5999-00-269-5320
NSN 5996-01-136-5730
NSN 6685-01-542-1466
NSN 5895-01-107-8547