Damper Product Line Capabilities and Variations Spunstrand® Inc. manufactures both Zero-Leak (ZL) and Balancing Dampers (BA) for the corrosive fume handling industry for a variety of environments and applications. These dampers can be used to regulate air flow and/or isolate a particular part of a system. They are constructed of FRP providing a durable corrosion resistant product that can be used for numerous industrial applications such as: semiconductor manufacturing plants, wastewater treatment plants, pharmaceutical facilities, pulp and paper plants, metal plating ships and chemical facilities. The FRP duct industry's first Zero-Leak damper was installed in 1995 and patented by Spunstrand® Inc. . The damper was developed by Spunstrand® Inc.'s design team to be certified leak free through individual water testing. Each Spunstrand® Inc. ZL damper is manufactured with a resilient, machined rubber seat permanently formed into the duct wall. Balancing dampers are applicable where ultra low leakage is not critical. These leakage rates should not exceed 5%. Why Spunstrand Zero-Leak and Balancing Dampers?   Over forty years of FRP experience   100 millimeter RTP-1 quality clear liners   Balancing dampers available in sizes 2"-96" Ø   Better workmanship, individually quality tested   Delivered fully operational and tested   Zero-Leak dampers available in sizes 8"--96" Ø   Resistant to corrosion and environmental wear   Standard options other manufacturers charge for Damper Applications: Wastewater treatment plants   Laboratory exhaust   Micro-electronic plants   Aerospace industry   Food processing facilities Petrochemical plants   Glass and metal finishing   Pulp and paper industry   Automotive industry Process Examples: Scrubber and fan isolation   System balancing   Automated processes modulation   System cleaning Tool install or change out isolation   System shutdown   Clean room isolation Spunstrand® Inc.'s Zero-Leak and Balancing series dampers are manufactured under an ISO 9000 based Quality Assurance program. All dampers are inspected for quality, blade fit, range of operation, and each Zero-Leak damper is tested and certified leak free to 6" water column, and up to one psi when requested.