I found a product that does not block EMF, but is supposed to help the body react properly to them. I can't tell or prove that it is working fo me, and can't tell or prove that it is not. I call such products, subjective, meaning buyer beware. The only info, I can find, is from the vendor, Claris, but it sure seems to be very popular, and their info makes sense. It is a pendant which you wear as a necklace.

"The QLink "repairs and tunes" your Biofield and ensures its integrity. It "optimizes" and strengthens your external energy fields. Thus the QLink fortifies your Biofield against stress from all sources, and is able to maintain your balance and well-being.

When your Biofield functions optially, your whole being functions more optimally.
If disturbed, your overall balance is quickly reset, and imbalances quickly self-correct.
Your body's innate intelligence is enhanced.
Your body's natural ability to self-heal is strengthened.
Your whole system reorganizes at a higher level of performance - one that is more robust in creatively adapting to stress.

How can something so small and subtle do so much? An extremely weak field interaction occurs between the QLink and your Biofield - but poweful enough to enhance it. This is accomlished via a passive, non-invasive, and non-radiating method we call Sympathetic Resonance Technology (SRT™). Just as a guitar string resonates sympathetically with a tuning fork, your Biofield resonates sympathetically with the QLink.

When you wear the QLink, it resonates with your entire Biofield to maintain optimal strength, vitality and resilience in the presence of stress that threatens to damage and corrupt it.
http://www.emf-health.com/howqlinkworks.htm

"

"Clarus invents and manufactures new types of consumer and industrial products called sympathetic resonators. A sympathetic resonator creates a coupling circuit between subtle energies and classical electromagnetic energies. This coupling circuit does 3 important things.

It converts raw subtle energies into clarified, highly-delineated and highly-concentrated subtle energies. In the sense used here, "raw" is equivalent to raw materials that are converted from a relatively chaotic state into a more ordered, more refined state. After conversion, the subtle energies are, in effect, postulated to be more intensified and condensed.
It conducts these converted subtle energies into an environmental space. The size of the space can range from a 3 foot spherical radius to a 50 foot spherical radius. When the converted subtle energies are conducted into an environment, they act more directly than diffused or raw subtle energies on the systems they both comprise and influence.
This conversion and conduction actively effects the performance of phenomena in the influenced space - especially phenomena which employs electromagnetic fields."