FUNCTION: Maximizes the efficiency of your dust collection system by directing and regulating the air flow from one machine to another FEATURES: This self cleaning blast gate greatly reduces clogs or chip build-up, possesses an easy-sliding gate that slides through the housing and contains a built-in stop locking stop to perfect gate alignment QUALITY: Made with premium ABS plastic, this unit was designed for durability and is abrasion - to withstand daily wear & tear from dirt, sawdust and woodchips SPECIFICATIONS: Accepts 4Inch ID dust hose, port or vacuum fitting/Nominal end measures 3-61/64Inch O.D. and 3-3/4Inch I.D. Please note: the physical slightly color difference or difference, does not affect the use, please do not mind, thank you! Color:As Shown Material: ABS Package Contents: 2 * Dust Collector Blast Gate Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.