Exell Batteries not only provide consumers with high efficiency, long-lasting performance, they also function as replacement batteries for an array of common and unique applications. Exell Battery is one of the few product lines Proudly Assembled in the USA.Made with Alkaline cells, Exell Batteries will last longer and offer consumers excellent reliability. The A19PX or 531 is an unusual cell often used in older Polaroid cameras. It is a cylindrical battery with one mini snap connectors at each end (the same size of mini snap found in the popular 9Volt PP3 battery). The older Polaroid cameras models: 100, 101, 102, 220, 225, 230, 240, 250, and 340 use one PX19 or No. 531 (4.5 volt) alkaline battery.