Bar Maid Fly-Bye Floor Drain Trap Seal for 3.5" Drain Pipes

Equipped with a patented one-way valve that allows fluids to flow downward without restricting flow rate while preventing any backflow. Pesticide-free and VOC-free, this solution helps make drains virtually maintenance free and effectively blocks fruit flies and other insects from entering through the drain. It also acts as a vapor barrier to keep bacteria, odors, and gases contained, improving indoor air quality. No primers or fresh water are required.