ALEXANDRIA, Va., Sept. 23 -- United States Patent no. 12,421,709, issued on Sept. 23.
"Insulation disc for septic tank lid" was invented by Bernard C. Miller (Kimball, Minn.).
According to the abstract* released by the U.S. Patent & Trademark Office: "An insulating disc can be easily installed and removed from inside a riser of a septic tank. The insulating disc is seated atop an opening of the tank lid and seals around the riser inner surface. The disc can include a core formed of R-10 extruded polystyrene sandwiched between two layers of high-density polyethylene. A flexible gasket can extend outward from the disc to seal against the inner surface of the riser. Retention tabs can also be provided to center and hold the disc in place. Th...