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 5945-01-360-7424
NSN 5990-01-584-8363
NSN 5950-00-753-7577
NSN 5920-01-508-4243
NSN 5915-01-555-8852
NSN 6240-01-375-3571
NSN 6645-01-016-7706
NSN 5985-01-448-8992
NSN 6135-00-962-4111
NSN 6150-00-518-1402
NSN 6650-01-428-9958
NSN 5905-01-121-5468