Bar Maid Fly-Bye Floor Drain Trap Seal for 4" Drain Pipes

Features a patented one-way valve that allows fluid to flow freely downward without impeding flow rate while preventing any backflow. Pesticide-free and VOC-free, it helps make drains virtually maintenance free and effectively stops fruit flies and other insects from coming up through the drain. Acts as a vapor barrier to keep bacteria, odors, and gases contained in the drain, improving indoor air quality. No primers or fresh water are required.