It cannot protect against electrical products that leak electricity (power tools, refrigerators, microwave ovens, washing machines, televisions, video games, computers). It is necessary to ground the product to prevent leakage of electricity. (Even electric shocks that are not felt by the body can cause pacemakers, ICDs, etc. to malfunction.) It also cannot protect against electric shocks from devices that pass electric current through the body (body fat measuring devices, low-frequency therapy devices, electrotherapy devices).

There is no problem with magnets (large magnets, magnetic bedding mats or pillows, magnetic accessories) as long as they are not pressed directly against a pacemaker, ICD, etc.