These tool batteries fit Milwaukee cordless tools of a matching voltage and platform (e.g., M12 batteries for M12 tools, MX FUEL batteries for MX FUEL tools, and V18 batteries for V18 tools). Battery series are interchangeable within a platform. For example, an M18 tool can use any series of M18 battery (CP, XC, or HD). CP series batteries are lighter than XC and HD, so they’re used with drills, nailers, and when working overhead. XC series batteries have more power than CP and are used for circular saws and other high-draw tools. High-demand (HD) series batteries are used with heavy-demand tools such as chain saws and table saws. High-output versions of Milwaukee batteries have more power, run cooler, and are smaller and lighter than standard versions. Batteries of the same voltage, platform, and series may be available in different amp-hour (Ah) ratings. Batteries with higher Ah ratings have greater power storage capacity but are heavier than those with lower Ah ratings.