The DOYLE™ 1000V TRMS Auto-Ranging Digital Multimeter uses True-RMS averaging technology for precise measurements of complex waveforms. This professional precision multimeter is ideal for troubleshooting HVAC, automotive, and many other electrical and electronic systems. It has a simple-to-use interface with a large backlit display and professional-grade CAT IV 600V and CAT III 1000V safety ratings.