AstroAI 4000 Counts TRMS Clamp Meter The AstroAI True RMS 4000 Counts Digital CLAMP METER is designed to be safely and accurately used by professionals and weekend DIYer’s. It is suitable for commercial and household electrical problems. Advanced features have been provided including AC/DC Voltage, AC/DC Current, Frequency, Duty Cycle, Resistance, Capacitance Measurement and NCV Detection, Flashlight, Diode, Live Wire Test and Audible Continuity Testing.