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 5930-01-434-0679
NSN 6220-00-520-2603
NSN 6650-01-254-2744
NSN 6685-01-164-4901
NSN 6135-00-403-0213
NSN 6650-01-169-3885
NSN 5855-01-535-2266
NSN 5905-00-914-2982
NSN 5975-00-899-7952
NSN 4140-01-317-6441
NSN 5985-01-437-9733
NSN 6135-01-449-0625