Ideal 61-765 TightSight 660A TRMS AC DC Clamp Meter is a True-RMS meter that includes TightSight display on the bottom to provide convenient measurements in difficult to reach environments. Ideal 61-765 TightSight 660A TRMS AC DC Clamp Meter is a digital clamp meter providing measurements of AC/DC voltage, capacitance, resistance, continuity, AC/DC current and frequency.