An item consisting of a metal frame in which is inserted a flat metal plate mounted on a shaft. The plate, fluctuating automatically according to changes in atmospheric pressure, controls the stack or flue draft and maintains an absolute constancy of draft regardless of varying weather conditions.
NSN 5998-01-032-3299
NSN 5996-01-258-5327
NSN 6135-01-604-3956
NSN 6320-01-006-6138
NSN 5945-00-934-8045
NSN 5945-01-272-4414
NSN 5930-01-450-3635
NSN 6145-01-530-7171
NSN 6620-01-411-5750
NSN 6220-01-625-3533
NSN 6135-01-437-6409
NSN 2925-00-448-3102