Every duct system requires transitions or special adaptations - transitions to the collector or that special machine that just won't take a standard adapter. Therefore, it is not enough that you choose a supplier that can provide you with standard duct components. You must find an Industrial Duct Supplier that understands metal, how it works in the fabrication process, and how air flows in collection systems.
Dust Collection system design sometimes calls for a custom duct piece to connect the fan to the collector. US Duct can fabricate a precise transition to accommodate the design and/or brand of collector you are including with your system design.