Check the listing for details. WOODRIVER Dust Connection 4" OD Self Clearing ABS Blast Gate Fitting. Condition: New. Listed at 24.98 USD. NEW, WOODRIVER Dust Connection 4" OD Self Clearing ABS Blast Gate Fitting, 149576, Dust Collection Fitting, Self Clearing Blast Gate, ABS, 4-inch OD, 4'' Opening, Rugged ABS Plastic, Abrasion Resistant, These economical fittings will help you build a high performance dust extraction system for your shop. Made of ABS plastic (except for the aluminum blast gates), these fittings are designed to stand up against the abrasive nature of saw dust and wood fiber. Universal Tool Adapter adapts your wet/dry vacuum hose to stationary or portable power tools. It's constructed of a tough material and conforms to slight variations in size. The "stepped" design contains a 1", 1-1/4", 1-1/2" and 2" external diameter and a 1-1/4", 1-1/2" and 2-1/2" internal diameter connection. It also has a square flange.