The Exell A175 7.5v Alkaline Battery (TR175, MN175, 1501) is an alkaline replacement battery for the discontinued mercuric oxide cells like the 5MR44, 5H-C, 5NR44, and HM-5C. This A175 battery is wide used in pet collars, gun scopes, and microphones from products produced by companies such as UltraMax and Heckler & Koch. It is also used in various unique applications such as vintage cameras and complicated medical testing equipment. The Exell A175 7.5v Alkaline Battery (TR175, MN175, 1501) is a perfect replacement battery for older and discontinued mercuric oxide cells.