ABS construction Helps prevent sewer gas from entering your home Spring-loaded to open with negative pressure and close with positive pressure 1.5-In NPT In-Line Vent Mechanical Vent installs on the drain line and vents the line without allowing sewer gas to enter the home. Mechanical Vent installs on the drain line and vents the line without allowing sewer gas to enter the home. For venting sinks, tubs, showers, etc.
