The Lutron DM-9960 is a professional multimeter where working conditions require CATIII to 1000V. It is very economical and provides accuracy sufficient for almost all industrial trouble shooting applications. Further - a multimeter of this rating is a very safe option for trades where work is at a lower voltage such as domestic and HVAC. A full line of adaptors is available for other electrical and environmental measurements. For example AC/DC Clamp adaptors to 2000amps.