The M12B2 2.0Ah battery is compatible with all tools in the Milwaukee M12 range and offers great runtime in a small package. For instance, a fully charged 2.0Ah 12v battery holds enough charge to keep a M12HJBL4 Heated Jacket running for 8 consecutive hours. Alternatively the same battery would allow you to install 325 4.8mm stainless steel rivets with the M12BPRT pop rivet tool.