ALEXANDRIA, Va., Oct. 28 -- United States Patent no. 12,448,762, issued on Oct. 21.
"Dual air admittance valve" was invented by Michael Anthony Di Monte (Highlands, N.J.).
According to the abstract* released by the U.S. Patent & Trademark Office: "Embodiments of air admittance valve assembly and piping system incorporating the same are provided herein. In some embodiments, a valve assembly comprising a housing, a first valve comprising a first valve sealing member and a first valve seat, and a second valve comprising a second valve sealing member and a second valve seat, and a pipe, an inlet, an outlet, a first zone, a second zone, a third zone, the first and second valve sealing member is closed by gravity and open based upon the pressur...