This specification covers an industrial-grade modular stainless steel ductwork system for dust, mist, and fume collection, based on KB Duct (CECO Environmental) or approved equal. Components must use minimum Grade 304 stainless steel (Grade 316 acceptable), with clamp-together rolled lip connections for standard parts and factory-welded flanged ends for 28-inch large-diameter parts. The item list includes straight duct, branch fittings, elbows, reducers, adjustable sleeves, Forever clamps, and saddle hangers in sizes from 12 to 28 inches, with specified quantities. Required features include airtight welded seams, Buna-N and Neoprene gaskets, toggle-latch clamps, and field-adjustable telescoping sleeves. Substitutes must match or exceed the design and connect directly to standard industrial clamp-together duct lines without adapters.