Stetzerizer filters were developed by Dr. Martin Graham, professor emeritus from the University of California, Berkeley and Mr. Dave Stetzer, president of Stetzer Electric in Blair, WI, founded in 1974. Stetzerizer filters are the original filters for power line radiation reduction, and represent years of testing, design, and health studies. Scientists and researchers all over the world have used, tested, and published peer-reviewed studies based on Stetzerizer filters.

Because of the products' success, other companies have attempted to make imitations of Stetzerizer filters and benefit from the collaborative work of all the people associated with the Stetzerizer name. Some of these companies have even resorted to using misleading or flat out false information to try to market their knockoff filters. This page will set the record clear on the facts, so that you can make the right decision if you've been presented with knockoff filters.

We appreciate your continued support of Stetzerizer filters and the hard work and ongoing research of the individuals who have collaborated to develop this solution and continually advance the knowledge and research in the field of dirty electricity.

Knockoff Filters
Genuine Stetzerizer Filters

UL ApprovedNO. We haven't been able to verify the UL status of any knockoff filter.  Most knockoff filters have no safety certification.  We always recommend looking for the UL sticker on any product and contacting UL if you are unsure.
YES! Dave Stetzer went through the great expenses to obtain UL certification from the beginning.  Knowing it would be important for homeowners insurance, commercial insurance, and liability, UL is the standard in the US.  Always look for the UL logo on an electrical product.  Stetzerizer products have it!
Was developed by professionals doing documented research into dirty electricity.
NO. Knockoff filters were developed by people who came onto the scene later, after seeing the work done by Dave Stetzer, Dr. Martin Graham, and others.
YES! Dr. Martin Graham and Dave Stetzer developed these filters after extensive testing and hands-on research with animals and people who were suffering the ill-effects of dirty electricity. Dr. Graham and Mr. Stetzer reluctantly developed the filters because the electronics and power utility industries refused to take any steps to solve the problem themselves.
Instantly rendered safe when removed from outlet
NO. Many knockoff filters have not been designed properly and will maintain a charge after they are removed from the outlet. This charge could result in serious injury or death. It is NOT safe to touch the prongs after pulling out a knockoff filter. Children are especially at risk.
YES! Stetzerizer filters were designed properly and discharge instantly to ensure safety. This is another reason Stetzerizer filters are UL approved and knockoffs are not.
Has been studied and featured in published medical literature including medical journals.
NO. We have not seen a single published study done on knockoff filters. There seems to be no research done on knockoff filters. Knockoff filter sellers rely on the research that has been done on Stetzerizer filters. How are knockoff filters giving back to the community?
YES! Dozens of studies and papers have been published featuring Stetzerizer products. The developers of the Stetzerizer filters have assisted some of these studies by providing free filters and free placebo (for blind testing) filters. We continue to collaborate with researchers to always advance the science.
Has staff capable of answering highly-technical questions.
NO. Knockoff filter sellers have to defer to outside engineers for technical questions.
YES! Stetzerizer has full time staff trained in electrical engineering. Stetzerizer filters were developed in-house from the ground up in order to help people and solve a problem.
Has developed and currently provides filters for many countries, voltages, and outlet styles.
NO. Knockoff filters have not been designed, and are not sold in markets around the world.
YES! Stetzerizer is an international brand sold in many countries, for many outlet styles. They have been certified and approved for safe usage in markets around the world. They are a household, trusted name.
Non-polarized 2-prong design for versatile installation configurations.
NO. Some knockoffs are a 3-prong design that will cover an outlet if plugged into the top outlet. This can be a problem especially when top or bottom outlet is controlled by a switch.
YES! Stetzerizer filters are designed to plug right-side-up or "upside-down." They can be placed either way, and they will perform just as well! This allows more flexibility for many installations.
Solution-oriented company with old-fashioned business ethics and standards
NO. Knockoffs frequently market and sell their products making false assertions, stating false information, in a cunning attempt to mislead and sell their products..
YES! and Stetzer Electric are committed to helping people and will not mislead or misinform in order to make a sale.