Flat treatment pads versus bulky body coils?
One disadvantage of large coil systems is that the magnetic field is very localized and mainly within the coil area only. It is not suitable for full body energizing. Many manufacturers use the latter method because of technological difficulties in manufacturing and controlling high-density electrical currents within flat surface coils. Also, creating stable and effective electromagnetic fields exceeding the 10 milli Tesla (100 gauss) level seems to be problematic for other manufacturers.