![Amazon.com: OdorHog Vent Stack Pipe Filter 4 Sizes, Black ABS with Mushroom Cap, Removes Outdoor Septic and Sewer Odors (fits 1.5 or 2.0-inch) : Home & Kitchen Amazon.com: OdorHog Vent Stack Pipe Filter 4 Sizes, Black ABS with Mushroom Cap, Removes Outdoor Septic and Sewer Odors (fits 1.5 or 2.0-inch) : Home & Kitchen](https://m.media-amazon.com/images/I/615PzzTYRTL._AC_UF1000,1000_QL80_.jpg)
Amazon.com: OdorHog Vent Stack Pipe Filter 4 Sizes, Black ABS with Mushroom Cap, Removes Outdoor Septic and Sewer Odors (fits 1.5 or 2.0-inch) : Home & Kitchen
![What is this PVC pipe for? I'm thinking it has something to do with the septic system but the tank is about 20 feet away. There are no markings at all. : What is this PVC pipe for? I'm thinking it has something to do with the septic system but the tank is about 20 feet away. There are no markings at all. :](https://preview.redd.it/9hrau2d6j2451.jpg?width=640&crop=smart&auto=webp&s=bc37125b4cf2d7fccb027a0dfd3bada0b3cadf82)
What is this PVC pipe for? I'm thinking it has something to do with the septic system but the tank is about 20 feet away. There are no markings at all. :
![Active Ventilation 4 in. Dia Aura PVC Vent Cap Exhaust with Adapter for Schedule 40 or Schedule 80 PVC Pipe in Black AV-4-PVC-BL - The Home Depot Active Ventilation 4 in. Dia Aura PVC Vent Cap Exhaust with Adapter for Schedule 40 or Schedule 80 PVC Pipe in Black AV-4-PVC-BL - The Home Depot](https://images.thdstatic.com/productImages/675bd26e-6d3c-4334-8b15-2ab8baa1758c/svn/black-active-ventilation-static-roof-vents-av-4-pvc-bl-76_600.jpg)
Active Ventilation 4 in. Dia Aura PVC Vent Cap Exhaust with Adapter for Schedule 40 or Schedule 80 PVC Pipe in Black AV-4-PVC-BL - The Home Depot
![Purpose of septic vents both in the yard and also through the roof? - Home Improvement Stack Exchange Purpose of septic vents both in the yard and also through the roof? - Home Improvement Stack Exchange](https://i.stack.imgur.com/IzWId.png)
Purpose of septic vents both in the yard and also through the roof? - Home Improvement Stack Exchange
![Is this cap incorrect? Buying a new house and the Inspector said to remove it, but want to learn the 'why'. : r/Plumbing Is this cap incorrect? Buying a new house and the Inspector said to remove it, but want to learn the 'why'. : r/Plumbing](https://preview.redd.it/is-this-cap-incorrect-buying-a-new-house-and-the-inspector-v0-yehlewo3edbb1.jpg?width=1080&crop=smart&auto=webp&s=c5aad1c9ffc150576d0f889175ce74890f035975)
Is this cap incorrect? Buying a new house and the Inspector said to remove it, but want to learn the 'why'. : r/Plumbing
![Amazon.com: OdorHog Vent Stack Pipe Filter 4 Sizes, Black ABS with Mushroom Cap, Removes Outdoor Septic and Sewer Odors (4.0-inch) : Home & Kitchen Amazon.com: OdorHog Vent Stack Pipe Filter 4 Sizes, Black ABS with Mushroom Cap, Removes Outdoor Septic and Sewer Odors (4.0-inch) : Home & Kitchen](https://m.media-amazon.com/images/I/61eCCvDgzpL._AC_UF350,350_QL80_.jpg)
Amazon.com: OdorHog Vent Stack Pipe Filter 4 Sizes, Black ABS with Mushroom Cap, Removes Outdoor Septic and Sewer Odors (4.0-inch) : Home & Kitchen
![Oatey 3-in to 4-in x 4-in PVC Vent and Pipe Flashing in the Vent Pipe Flashing department at Lowes.com Oatey 3-in to 4-in x 4-in PVC Vent and Pipe Flashing in the Vent Pipe Flashing department at Lowes.com](https://mobileimages.lowes.com/productimages/ab601e1e-0ee7-41d8-8445-0fc526f176d6/64028366.jpg)