Great tool for accurate measurement of low current. Use with your graphing meter or lab scope to view current waveforms on fuel injectors, fuel pumps, primary ignition coils and more. Also works very well with digital multimeters. Resolution of 10 milliamps is low enough for most parasitic drain testing. In addition, the clamp opening of 1/2 inch is large enough to clamp over most negative battery cables for those parasitic drain tests.