Energizer Holdings, Inc. is an American manufacturer and one of the world's largest manufacturers of batteries, headquartered in St. Louis, Missouri. It produces batteries under the Energizer, Ray-O-Vac, Varta, and Eveready brand names and formerly owned several personal care businesses until it separated that side of the business into a new company called Edgewell Personal Care in 2015.

Spectrum Brands Holdings, Inc. is an American diversified company headquartered in Middleton, Wisconsin. It was established in 2005 as the successor to Rayovac Corporation. It is one of the Fortune 500 companies, and among the largest of its kind.