AEMC 403 [2139.21] 1000V AC / DC, 1000A AC / 1500A DC True RMS Clamp-On Meter, 1.89" Jaw Size. The TRMS Clamp-on Meter Model 403 provides a new standard for safety and measurement capability not available in any other clamp meter sold today. Safety Rated at 1000V CAT IV, it is safe to operate in all electrical environments. It is rugged enough for the most demanding work environments and will withstand both dust and water spray with its IP54 rating. It is ergonomically designed and easily used by one hand, including function selection and button pushing even with a glove on. In addition to the standard measurement of volts, amps, frequency, resistance, diode checking and continuity, the Model 403 offers several unequaled functions including: True InRush®, Adapter function, Delta relative function, Temperature measurement and more.