Procell Alkaline Constant 9V industrial batteries are ideal for powering low drain professional devices which require constant current over a long period of time such as smoke/carbon monoxide detectors. Manufactured using superior cell design (vs. prior Procell Alkaline 9V batteries) to ensure high-quality cell construction. Each battery comes with a ‘quality warranty’. Design, safety, manufacturing, and qualification follow Procell’s stringent battery standards, which incorporate parts of the ANSI and IEC battery standards.