Clamp-Style Metal Ductwork with Rolled Ends in Spiral or Longitudinal seams for use in Industrial and Commercial Dust Collection Systems namely, ducts, pipes, couplings, elbows, joints, collars, connectors, and fittings made wholly or principally of metal

Clamp-Style Metal Ductwork with Rolled Ends in Spiral or Longitudinal seams for use in Industrial and Commercial Dust Collection Systems, namely, ducts, pipes, couplings, elbows, joints, collars, connectors, and fittings made wholly or principally of metal