There are two insert (ms21209f1-15l)included with standoff
A standoff that must have a threaded end(s) or be internally threaded its full length. For items having external threads on both ends, see stud (as modified). For items with an outside contour that is the same for the entire length, are flat on top and bottom, having internal threads its full length, and the length does not exceed twice the width across the flats or outside diameter, see nut (as modified); use maximum dimensions(s) for compliance.
NSN 5996-01-388-7618
NSN 5835-00-665-3395
NSN 7035-00-929-0363
NSN 6685-01-088-0213
NSN 2925-00-456-7627
NSN 6610-01-083-1528
NSN 5950-01-063-3825
NSN 5835-01-470-7700
NSN 5999-00-826-8451
NSN 5985-00-928-8242
NSN 6240-01-492-5045
NSN 6240-01-299-2335