Add an in-line back blast damper to your dust collection system to reduce backward air flow in the line. Nordfab QF in-line back blast dampers are designed to be used within a horizontal line; however, vertical operation can be designed if required. Shop Wurth Baer Machinery for all of your in-line back blast damper needs and dust pipe and dusting needs. We offer a complete line of Nordfab QF dust pipe components and accessories.