Klein Tools CL600 Electrical Tester is an automatically ranging true mean squared (TRMS) digital clamp meter measures AC current via the clamp, and measures AC/DC voltage, resistance, continuity, and tests diodes via test-leads. Exclusively designed from the ground up by electricians for electricians. Years of field research, combined with extensive input from electricians across America, inspired the development of meters loaded with innovative, time-saving features.