A close-coiled helical extension spring, with ends fastened together to form a circle, designed to impose compression stresses toward the center of the circle thus formed when uniformly expanded.
NSN 4140-01-602-8454
NSN 5990-00-419-0236
NSN 6610-01-365-6504
NSN 5950-01-384-3240
NSN 6685-00-151-5257
NSN 6220-01-123-1353
NSN 6240-01-026-1376
NSN 6650-01-317-2101
NSN 5950-01-175-1620
NSN 6645-01-088-5244
NSN 6645-01-282-3624
NSN 4140-01-202-1032