OdorHog is an activated charcoal vent stack filter for plastic or metal vent pipes that eliminates unpleasant outdoor odors from the roof vents Fast installation, no glue required, choose from 5 sizes. This Slip-on model fits on standard Schedule 40 PVC or ABS vent pipes with no tools or glue required. If you have metal, cast iron or non-standard PVC/ABS pipes, order the Clamp On model ASIN: B08X1DYTP3 Proudly made in the USA, OdorHog is built strong with PVC plastic to withstand the sun and weather, our mushroom cap design keeps out water, leaves, and debris. OdorHog comes ready to use with activated carbon filter bag. Earth-friendlier than disposable filters, our clean and easy-to-replace mesh replacement bags contain superior, activated carbon that lasts years, not months Please measure your vent stack pipe before ordering an OdorHog. See graph/video on how to measure. OdorHog is not recommended if you have indoor plumbing odor issues.