USED Original Air Registration Board (ARB) General Purpose Maintenance Schedule for Helicopters p/n: n/a Sec/ref: n/a NSN: n/a qty: 1 Plain length: n/a Thread length: n/a In good condition, listed as used but think un-used but grubby and slight damage from storage. Not checked for completeness Issue 1 dated March 1971 Please see pictures for items covered and condition.
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