Reference parts book 0532-lp-103-0916, section 6, page 93, figure 6.44, item 15
A nonmetallic circular item with an aperature, having a solid round cross-section. They are used primarily for sealing. For items with other than round cross section, see packing,preformed. For noncircular items with a round cross-section, see seal,nonmetallic round section and rubber,round section.
NSN 5930-00-762-0562
NSN 6150-00-222-5302
NSN 6620-00-257-2783
NSN 5990-01-381-9526
NSN 5915-01-464-3853
NSN 5930-01-288-4162
NSN 7035-01-408-3699
NSN 5990-01-257-6854
NSN 6620-01-439-9471
NSN 5925-01-519-9251
NSN 5895-01-389-6317
NSN 6650-01-579-3855