Great for accurate measuring of low amps. Has low reading capability of 1 milliamp (0.001 A). Unit also features full function DMM built in. Data hold, Auto power off and backlit LCD display. Zippered carrying case and test leads included With the capability of measuring down to 1 milliamp (.001A), the ESI687 is a great tool for all low current applications. Especially for diagnosing parasitic drains! Clamp opening is large enough to fit over most negative battery cables. Applications: fuel injectors, fuel pumps, electric motors, battery drains, charging systems. Other functions include: Continuity beep, overload protection, clamp opening: 5/8". 9 volt battery is included.