How Studor® Air Admittance Valves Work
When a plumbing fixture is operated and water drains out of the system, negative pressure causes the valve to open, allowing air to enter as needed to equalize the pressure and protect trap seals from siphonage. When the flow stops, gravity closes the valve, preventing the escape of sewer gases through the valve.

Air Admittance Valves by STUDOR®
	These air admittance valves feature: Pressure sensitive valve Opens upon fixture discharge Admits air into drain, waste and vent systems Closes to prevent foul air inside Can be used as individual, branch, circuit or stack vent Expands architectural design limits Reduces the number of fire-stopping applications Exclusive vermin protection system Limited lifetime warranty for replacement of defective valves Should not be exposed to outdoor elements Considered "the standard" by some No roof penetration NSF Standard 14 ASSE 1051, 1050 rated IAMPO Classified Marking
Mini-Vent - will vent up to 24 DFUs on stack - click for dimensions Price & Quantity Mini-Vent® for 1 1/2" or 2" pipe - each $26.95 Mini-Vent® for 1 1/2" or 2" pipe - 6 ea. (CASE QTY) $152.95   Maxi-Vent - will vent up to 500 DFUs on a stack - click for dimensions Price & Quantity Maxi-Vent® for 3" or 4" pipe (vent stack) - each $38.15 Maxi-Vent® for 3" or 4" pipe (vent stack) - 6 ea. (CASE QTY) $218.95 NOTE: For 3" vent, a hubless coupling #NH30 will be needed - Or -

Multi-Purpose* Recess Box by Studor® For Mini-Vent
Mini-vent inside recess box	Mini-vent inside recess box with grill cover
The Mini-Vent may be installed inside or outside using the Multi-purpose Recess Box. It has "cut-outs" to allow in-wall installation on 1-1/2", 2", and 3" pipes. This multi-purpose recess box features: Allows in-wall mounts Outdoor use (side-wall venting) Alternative to venting through the roof * May be used as a washing machine box
Description Price & Quantity Studor® Multi-Purpose Recess Box with grill and screws - for Mini-Vent $17.95 - Or -

Sure-Vent® Air Admittance Valves by Oatey®
click here	This air admittance valve features: Pressure sensitive valve Opens upon fixture discharge Admits air into drain, waste and vent systems Closes to prevent foul air inside No roof penetrations NSF compliance listing to NSF Standard 14 Glues into both 1-1/2" and 2" PVC (and threads into 2") ANSI/ASSE 1050, 1051 rated for 1-1/2" thru 4" diameter Handles up to 15 psi positive pressure Does not need cold weather protection Should not be exposed to outdoor elements Manufacturer recommends at least one vent stack to open air Not as large as the Studor® Maxi-Vent® (above)
Description Price & Quantity Sure-Vent® each $28.95 Sure-Vent® 6 ea. (CASE QTY) $155.95 - Or -

1-1/2" Auto Trap Vent
	This auto trap vent features: Generally used in mobile homes and places where mechanical venting is impossible to install Operates with a spring
Description Price & Quantity 1-1/2" Auto Trap Vent $2.95 - Or -

STUDOR® Maxi-Filtra™
	The STUDOR® Maxi-Filtra™ operates as a two way vent, which filters air in both directions. Its active carbon filter is designed to eliminate bad odors produced by the plumbing drainage system. The Maxi-Filtra™ is for outdoor use only, particularly for use with septic systems, but can also be installed on existing open vent pipes and in systems in which air admittance valves (AAVs) are installed.
This vent pipe filter features: Can be installed vertically or horizontally Outdoor use only Contains a carbon filter that can last up to two years Fits 3" or 4" pipe
Description Price & Quantity Maxi-Filtra™ air vent filter for 3" or 4" pipe Order 6 (case qty) or more for greater savings! $43.95 - Or -

We recommend using non-mechanical venting wherever possible.
The main reason is that (all brands of) mechanical vents can/will eventually fail.
We recommend plumbing your vents to the outside, per your local codes.
- using the above-mentioned mechanical vents are not code approved in all areas -

The Studor® valves may not be returned.
Studors have a lifetime warranty with the manufacturer.

Note: all of these above are mechanical vents.
In our opinion all brands of mechanical vents can (eventually) fail.