The eddy current flaw detector is a device based on the principle of eddy current testing to detect the presence of cracks, pores and other defects in steel bars and plates. 

It has the function of suppressing interference signals and picking up useful information. The instrument consists of an oscillator, a probe coil, and a signal detector. It is composed of equipment, measurement and comparison circuit, signal processing alarm display and power supply, etc. It is mainly used for nondestructive testing of metal materials.