Spindle dia 75mm 80mm 85mm 90mm 100mm 4 inch dust port dust collection system spindle dust cover for cnc router machine. Up-down design, the brush will not be deformed. Always protect the brush from damage and the brush is level with the knife. Removable on all sides, lightly pressed, lightweight and convenient. The flat suction port is better designed and stronger (elliptical suction port diameter 100mm). Size Chart: Diameter: 70mm/2.76inch 75mm/2.95inch 80mm/3.15inch 85mm/3.35inch 70mm/2.76inch 100mm/3.94inch Package Includes: 1x Spindle Dust Cover Shoe Note: 1. Please allow slightly error due to manual measurement. 2. Due to the difference between different monitors, the picture may not reflect the actual color of the item. 3. Wish you a wonderful online shopping!