239 Sioux Chief 1-1/2" MIP Anti-Siphon Auto Vent - Air automatically enters drain line for proper venting, then the spring-loaded seal closes after drainage to prevent escape of sewer gases
 - For secondary venting only. Each drainage system must have a main vent stack
 - To be installed in a readily accessible location with free flow of air, never in a sealed wall cavity
 - Sealing disc of auto vent must be located at least 6" above the top of the trap arm
 - Two fixtures may be drained by a common 1½" drain pipe. Three or more fixtures will require a 2" drain pipe
 - 1-1/2" MIP vent ABS