Transmitters, including cell phones, emit radio signals on more than the assigned frequency. These other signals on other frequencies are “harmonics” and/or “noise” and/or “dirty” signals from less than optimal transmitters, antennae, and/or resonating frequencies emitted from metallic objects in close proximity to the transmitter, like the other components of the cell phone.
I debated whether to give it 3 or 4 stars: on features, speed of delivery, and quality of construction, it definitely deserves 4 stars. If I can measure and verify the emf reduction, then I will change the rating to 5 stars. Since the whole point of using it is to block excess em radiation, I can't really give it 5 stars without more proof that it really does so.
Exposure to ionizing radiation, such as from x-rays, is known to increase the risk of cancer. However, although many studies have examined the potential health effects of non-ionizing radiation from radar, microwave ovens, cell phones, and other sources, there is currently no consistent evidence that non-ionizing radiation increases cancer risk in humans (2).
Whether you call them cell phones, smart phones or mobile devices, it seems like everyone has one. According to the wireless telecommunications industry, the U.S. now has an estimated 300 million mobile subscribers, compared to 110 million subscribers a decade ago. The increase in cell phone use has generated concern about possible health risks related to radiofrequency electromagnetic fields from this technology, and a market for shields as possible protection against the radio waves the phones emit. The Federal Trade Commission (FTC), the nation's consumer protection agency, has some practical tips to help you avoid scams and limit your exposure to electromagnetic emissions from your cell phone.
Current regulatory standards (SAR Test) only protect us from thermal or heating risks; yet, many hundreds of laboratory studies have found that low-intensity, non-thermal exposure to cell phone radiation can promote carcinogenic mechanisms. Moreover, research on humans has found that 25 years of mobile phone use is associated with a three-fold risk of brain cancer.  –Joel M. Moskowitz, Ph.D. School of Public Health. University of California, Berkeley
We’re also exposed to radio-frequency radiation from the networks that connect our phones. And while the coming rollout of 5G, or fifth-generation, wireless networks is expected to transmit data faster than ever, it will also increase the number of antennas sending signals to mobile devices, and potentially our exposure to radiation, with unclear health effects.
In addition to the increased brain cancer risk, in male rats there was also “clear evidence” of a link between the radiation and malignant heart tumors and “some evidence” of a link to adrenal-gland tumors, according to the release. In mice and in female rats, however, the link between radiation and tumors was “equivocal,” or uncertain. The hierarchy, from most to least certain, of characterizations used by the NTP is: “clear evidence”; “some evidence”; “equivocal evidence”; and “no evidence.”Today’s cellphones use higher-frequency radiation that is less able to penetrate animal tissues than the radiation used in the study, the Times reports. Further, since cellphones became popular, epidemiologists have not observed an overall increase in the frequency of brain cancers known as gliomas in humans. 
A carrier wave oscillates at 1900 megahertz (MHz) in most phones, which is mostly invisible to our biological tissue and doesn’t do damage. The information-carrying secondary wave necessary to interpret voice or data is the problem, says Dr. Carlo. That wave cycles in a hertz (Hz) range familiar to the body. Your heart, for example, beats at two cycles per second, or two Hz. Our bodies recognize the information-carrying wave as an “invader,” setting in place protective biochemical reactions that alter physiology and cause biological problems that include intracellular free-radical buildup, leakage in the blood-brain barrier, genetic damage, disruption of intercellular communication, and an increase in the risk of tumors. The health dangers of recognizing the signal, therefore, aren’t from direct damage, but rather are due to the biochemical responses in the cell.
In 2015, the European Commission Scientific Committee on Emerging and Newly Identified Health Risks concluded that, overall, the epidemiologic studies on cell phone radiofrequency electromagnetic radiation exposure do not show an increased risk of brain tumors or of other cancers of the head and neck region (2). The Committee also stated that epidemiologic studies do not indicate increased risk for other malignant diseases, including childhood cancer (2).
But there is also some ambiguity about cellphone radiation’s health effects. As Dr. John Bucher, a senior scientist at the National Institute of Environmental Health Sciences and a co-author of the NIH studies, told me, “[Our results] go against the notion that non-ionizing radiation is completely harmless.” In other words, he’s found that the type of radiation cellphones give off could cause biological changes, like promoting tumors, at least in animals.
Specific Absorption Rate (SAR) is an indicator for calculating the level of radiation absorbed in the body. This indicator represents the rate of energy absorption by the tissue and is expressed in units of Watt/kg. The Consumer Protection Regulations (information on non-ionizing radiation from mobile phones) of 2002, stipulate the duty to label the product, specifying the radiation level of the phone’s model and the maximum permitted radiation level. This regulation allows to compare the emitted radiation level between different instruments and to take this into consideration when weighing the factors determining the choice of a new instrument at the time of its purchase.
Yes, the information transferred between the base unit (the phone’s stationary unit) and the wireless phone’s mobile unit is transferred as radiowave radiation. Therefore, the “precautionary principle” should also be adopted regarding wireless phones. In addition to the guidelines regarding mobile phones, the Ministry of Health recommends regarding wireless phones:
Use the speaker mode on the phone or a hands-free device such as a corded or cordless earpiece. This moves the antenna away from your head, which decreases the amount of RF waves that reach the head. Corded earpieces emit virtually no RF waves (although the phone itself still emits small amounts of RF waves that can reach parts of the body if close enough, such as on the waist or in a pocket). Bluetooth® earpieces have an SAR value of around 0.001 watts/kg (less than one thousandth the SAR limit for cell phones as set by the FDA and FCC).

What are the health effects of mobile phones and wireless radiation? While Australia has led the world in safety standards, including compulsory seat-belt legislation, plain packaging on cigarettes, and product and food disclosure legislation, it falls behind in addressing the significant issues associated with mobile phone use. In this Dean’s Lecture, epidemiologist and electromagnetic radiation expert, Dr Devra Davis, will outline the evolution of the mobile phone and smartphone, and provide a background to the current 19 year old radiation safety standards (SAR), policy developments and international legislation. New global studies on the health consequences of mobile/wireless radiation will be presented, including children’s exposure and risks.

“When symptoms are not addressed comprehensively– for example, using symptom amelioration without simultaneous elimination of exposure – cell membrane adverse reaction and damage continue to occur while the patient is assuming the cause of the problem has been eliminated. This lulls patients into a false sense of security, causing them to aggravate their exposures through the increased use of their wireless devices. When the damage reaches a critically harmful level, even the symptom amelioration can no longer be sustained by the damaged cells.”

In 2011, researchers at the National Institutes of Health showed that low-level radiation from an activated cell phone held close to a human head could change the way certain brain cells functioned, even without raising body temperature. The study did not prove that the effect on brain cells was dangerous, only that radiation from cell phones could have a direct effect on human tissue.

Dr. Carlo, wrote a  Medical Alert ten years ago. He cautioned people with EMF sensitivity against relying upon widely-available EMR Protection Products to prevent the effects of EMF exposure. He noted that EMF sensitive individuals were reporting the opposite effect: people found their symptoms and/or sensitivity worsened. Specifically, severe “symptom relapses.” Dr. Carlo noted:
What are the health effects of mobile phones and wireless radiation? While Australia has led the world in safety standards, including compulsory seat-belt legislation, plain packaging on cigarettes, and product and food disclosure legislation, it falls behind in addressing the significant issues associated with mobile phone use. In this Dean’s Lecture, epidemiologist and electromagnetic radiation expert, Dr Devra Davis, will outline the evolution of the mobile phone and smartphone, and provide a background to the current 19 year old radiation safety standards (SAR), policy developments and international legislation. New global studies on the health consequences of mobile/wireless radiation will be presented, including children’s exposure and risks.
My iPhone 6s easily snapped into place. The case is attractive AND I can find my phone more easily than when I had no case. (There have been times when my slim iPhone got lost among a collection of papers. The case makes the phone more visible because of the case color and because it is thicker than the uncased phone.) I like the loop that you can attach to the case if you want to hang it on your wrist. Best of all, I am pleased about the radiation protection.
Asked about his own cellphone use, Dr. Bucher said he had never been a heavy user but, in light of the study, was now “a little more aware” of his usage. On long calls, he said, he tried to use earbuds or find other ways “of increasing the distance” between the cellphone and his body, in keeping with advice issued to consumers about how to lower their exposure.
Please research info supplied by Dr Patrick Flanagan on the One Radio Show last November? He said during the interview that Ferric Oxide Crystals have the same earth Schumann Resonance and can be easily and cheaply bought as Jewellers Rouge. You can simply add some to clear nail varnish and dot all your electricals with it. To neutralise a Smart Meter you should paint the wall in between. I know it works and within a few days of doing this plus painting stones and throwing them (gifting) in close prox of mobile masts black helicopters started harassing me!
The 13-country INTERPHONE study, the largest case-control study done to date, looked at cell phone use among more than 5,000 people who developed brain tumors (gliomas or meningiomas) and a similar group of people without tumors. Overall, the study found no link between brain tumor risk and the frequency of calls, longer call time, or cell phone use for 10 or more years. There was a suggestion of a possible increased risk of glioma, and a smaller suggestion of an increased risk of meningioma, in the 10% of people who used their cell phones the most. But this finding was hard to interpret because some people in the study reported implausibly high cell phone use, as well as other issues. The researchers noted that the shortcomings of the study prevented them from drawing any firm conclusions, and that more research was needed.
The World Health Organization states that "A large number of studies have been performed over the last two decades to assess whether mobile phones pose a potential health risk. To date, no adverse health effects have been established as being caused by mobile phone use."[2] In a 2018 statement, the FDA said that "the current safety limits are set to include a 50-fold safety margin from observed effects of radiofrequency energy exposure".[3]

RF waves from cell phones have also been shown to produce “stress” proteins in human cells, according to research from Martin Blank, Ph.D., a special lecturer in the department of physiology and cellular biophysics at Columbia University and another signer of the recent letter to the WHO and U.N. “These proteins are used for protection,” Blank says. “The cell is saying that RF is bad for me and it has to do something about it.”
So, you've read the numerous studies about the potentially harmful health effects of cell phone radiation and you are ready to something about it. Of course, you can use your phone sparingly and put it in airplane mode when possible, use a wired headset or speakerphone when on calls, and never store it in your pocket. However, is that realistic? How about for your kids? In today's world, with our increasing dependence on our cell phones, probably not!
Jump up ^ For example, Finland "Radiation and Nuclear Safety Authority: Children's mobile phone use should be limited". Finnish Radiation and Nuclear Safety Authority (STUK). 7 January 2009. Archived from the original on 11 January 2010. Retrieved 20 January 2010. and France "Téléphone mobile, DAS et santé" [Mobile telephones, SAR and health] (PDF). Votre enfant et le téléphone mobile [Your child and mobile telephony]. Association Française des Opérateurs Mobiles (AFOM)[French Mobile Phone Operators' Association] et l’Union Nationale des Associations Familiales (UNAF) [National Federation of Family Associations]. 31 January 2007. Retrieved 20 January 2010.
Cables can act as an antenna, especially if they pass close to a strong source of radiofrequency radiation. One study has suggested that if the cable of a hands free mic passes near the phone's antenna, it can pick up some radiation and transmit it to your ear. Our ferrite snap bead is designed to reduce RF radiation in the cable. Made in 2 halves, you simply press it around the hands free wire at any convenient location near the earpiece end. Couldn't be simpler. It is small and lightweight enough to be almost unnoticable, yet powerful enough (50 ohm impedence minimum) to control nasty radiation. These are brand new, top quality and will accommodate wires up to 5 mm (3/16 inch) in diameter. About 1 inch long, grey color. If you are concerned about radiation from your hands free ear mic, this is the answer. Useful from 200-1000 MHz.

A recent small study in people has shown that cell phones may also have some other effects on the brain, although it’s not clear if they’re harmful. The study found that when people had an active cell phone held up to their ear for 50 minutes, brain tissues on the same side of the head as the phone used more glucose than did tissues on the other side of the brain. Glucose is a sugar that normally serves as the brain’s fuel. Glucose use goes up in certain parts of the brain when it is in use, such as when we are thinking, speaking, or moving. The possible health effect, if any, from the increase in glucose use from cell phone energy is unknown.
To check for radiowave emissions, use an RF meter with Near Field antenna. Again, position the antenna loop on the phone (because the entire antenna stem has some sensitivity, it is best to position the entire antenna over the area that will be shielded). Note carefully where the loop is positioned. Make a call and watch the readings. Notice the highest and lowest readings, and make a mental note of the "average" reading. Now, insert the shield, and repeat.
"To expect relief from radiation exposure from one specific device, is nearly impossible. It’s crucial to weigh in the MANY environmental factors; such as, temperature, atmospheric pressure, other radio waves, emissions from other devices, energy shifts from others around you, and Schumann Resonance shifts. Therefore," he explains that “relying on alteration of the environment as a safety precaution is always a game of chance…and signals affect people differently,” which adds another variables in the game of chance.
In subsequent analyses of Interphone data, investigators addressed issues of risk according to specific location of the tumor and estimated exposures. One analysis of data from seven of the countries in the Interphone study found no relationship between brain tumor location and regions of the brain that were exposed to the highest level of radiofrequency radiation from cell phones (9). However, another study, using data from five of the countries, reported suggestions of an increased risk of glioma and, to a lesser extent, of meningioma developing in areas of the brain experiencing the highest exposure (10).