This is a dust boot system made out of 1/2" clear Plexiglass with a magnetic removable base that holds a transparent flexible screen that allows you to see what you'r cutting/engraving tool is doing. Magnetic base is easily removed that allows for full access to tool install. Design to fit a the spindle/router size selected and will accept a 2-1/4" standard shop-vac hose or 2-1/2" Ultra Flex PVC hose. - Note: for 4" vac port, see item #B0D8V2RJHH