The Extech CG204 is a portable meter designed for non-invasive coating thickness measurements with automatic recognition of ferrous and non-ferrous substrates. The tester uses dual technology to indicate ferrous (magnetic induction measurement) and non-ferrous (eddy current measurement) substrates. It features single and continuous measurement modes as well as direct and group working modes, 400-reading memory storage, and user-programmable high/low alarms. The CG204 comes with two AAA batteries, USB cable, software, calibration iron, calibration aluminum, precision standards, pouch case, and user manual.