A Stetzer filter (often branded as a STETZERiZER® Filter) is a plug-in electrical device designed to reduce “dirty electricity”—high-frequency electrical noise and harmonic distortion that can ride along standard AC power wiring in homes and buildings. These filters contain specialized circuitry (usually capacitive components) that are intended to smooth out or absorb high-frequency transients and spikes on indoor wiring, helping lower the amount of electrical interference present on power lines. You plug them into a standard outlet, and when used with multiple units across a space, they’re meant to collectively reduce the overall level of this noise.
Stetzer filters are frequently paired with a Stetzer Microsurge Meter, which measures dirty electricity in “GS units” and helps users determine where filters might be most effective and whether additional filters are needed to lower electrical noise.
Some people use these plug-in dirty electricity filters as part of an EMF or power-quality strategy in homes or offices to help create a calmer electrical environment, particularly where modern electronics, energy-efficient lighting, and switch-mode power supplies produce a lot of high-frequency distortion.
