Used on helicopters (h1). navy: washer, aircraft equipment inside diameter is 0.203 inch; next higher assy is duct assy, air conditioning-heating; nsn's 1560-01-256-7631 & 1560-01-290-6522; essential to weapon system performance or operation, or the preservation of life or safety of operating personnel passivate surface treated
Used on h1 helicopter. navy: washer, special, aircraft inside diameter is 0.390 inch; next higher assy is stabilizer bar assy; nsn 1650-01-074-2848 passivate surface treated
Used on non jsl items - helicopters (h1). navy: washer, aircraft equipment inside diameter is 0.140 inch; next higher assy is duct assy, air conditioning-heating; nsn's 1560-01-256-7631 & 1560-01-290-6522 passivate surface treated
