Selective comparative magnetometer CM 455 is a magnetic field meter that radiates antennas of magneto-therapeutic and biorezonance devices. Typically, for example: Plasma generator, RaMaLoop, PlasmaLoop, MTE-14 and others similar to them. The CM 455 was developed by BTV company in order to highlight alternating magnetic fields of low and medium frequencies that are otherwise difficult to measure. Attention! The CM 455 is not identical to the DT-1130 electromagnetic smog detector, however the CM 455 reminds of its DT-1130 design. Both devices are completely different in principle, although they use the same cabinet and display and can not be interchanged. For many reasons, the CM 455 magnetometer does not work for measurement in a wider spectral view. The measurement is selective on the frequency of 455 KHz +/- 5 kHz and is only indicative. However, even this comparative measurement is sufficient to detect the radiation characteristics of magnetotherapeutic and biorezonance devices and to compare their emitted power. The CM 455 can also be used to monitor their basic functions online - generating alternating magnetic fields.