"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.
So of course now that we understand that the cases are not tested and just the material--it makes sense! We measured power density levels all around the case-the shielding material most likely isn't used "all over" because then the phone couldn't receive signal and wouldn't be able to engage in a call.  That's why we did not see even close to a 99% reduction when some cases were on the phone.  In fact, watch the video and you'll see some readings are more than 20% higher with a case on vs the naked phone.
Take a closer look at the product claims. Many refer to their “shielding technology” and not the product itself. In many cases, the “FCC Certified” labs they cite are actually testing how much RF the raw shielding material can block. They’re testing the materials used in the products. They’re not testing how much RF the actual products block while on a real-world phone.
Don’t be mislead by a common misconception started in the 90′s that wired headsets, that the headset that came with your cell phone is a safe alternative to placing a phone to your head.   This is simply not true at all! Ordinary headsets use a wire to deliver sound to an electronic earpiece that can deliver electromagnetic radiation into your head directly through your ear canal.
Cell phones work by sending signals to (and receiving them from) nearby cell towers (base stations) using RF waves. This is a form of electromagnetic energy that falls between FM radio waves and microwaves. Like FM radio waves, microwaves, visible light, and heat, RF waves are a form of non-ionizing radiation. They don’t have enough energy to cause cancer by directly damaging the DNA inside cells. RF waves are different from stronger (ionizing) types of radiation such as x-rays, gamma rays, and ultraviolet (UV) light, which can break the chemical bonds in DNA.
This is a 2 pieces of plastic sandwiched together by glue. Don't believe me? Take it apart. This item works no better than the existing case on your phone. If you are that concerned with cellphone radiation, you should be equally concerned about the cheap plastic and toxic glue that this is comprised of. Also know the fact that they've stolen $25 from your wallet when you purchase this hokey product...Technology at it's finest.
“It’s quite informative that the NTP data found evidence of an increased tumor risk in the male rats for glial cells and in the [heart] Schwann cells,” said Joel Moskowitz, director of the Center for Family and Community Health at the Berkeley School of Public Health (who writes about electromagnetic radiation here). “That’s compelling evidence that what we’re seeing in humans — even though the signal is not clear — is highly suggestive, and that there is indeed something real going on with regard to tumor risk in humans.”

SafeSleeve was founded in California by two Engineering graduates (University of Cal Poly San Luis Obispo) Cary and Alaey, with a desire to make a difference. They wanted to develop a product to help simplify, protect, and enhance the lives of their increasingly busy, tech dependent peers, family and friends. This is apparent in the highly efficient and useful, yet stylish designs and branding of SafeSleeve products. 
The government’s policies must change. Cell phone users should make their voices heard to prompt the FCC and manufacturers of cell phones and cases to ensure that these accessories never increase and, to the extent possible, decrease, users’ radiation exposure. At minimum, the FCC must take cell phone cases into consideration when it updates its standards to ensure that the use of a case will not expose people to more radiation than its legal SAR limit.  
According to the WHO, the "precautionary principle" is "a risk management policy applied in circumstances with a high degree of scientific uncertainty, reflecting the need to take action for a potentially serious risk without awaiting the results of scientific research." Other less stringent recommended approaches are prudent avoidance principle and as low as reasonably practicable. Although all of these are problematic in application, due to the widespread use and economic importance of wireless telecommunication systems in modern civilization, there is an increased popularity of such measures in the general public, though also evidence that such approaches may increase concern.[35] They involve recommendations such as the minimization of cellphone usage, the limitation of use by at-risk population (such as children), the adoption of cellphones and microcells with as low as reasonably practicable levels of radiation, the wider use of hands-free and earphone technologies such as Bluetooth headsets, the adoption of maximal standards of exposure, RF field intensity and distance of base stations antennas from human habitations, and so forth.[citation needed] Overall, public information remains a challenge as various health consequences are evoked in the literature and by the media, putting populations under chronic exposure to potentially worrying information.[36]

Some products (http://www.safecell.net/reports01.html for example) are tested using a piece of shielding material in a laboratory test jig. These tests legitimately show the amount of radiation which penetrates the shield, but results will be very different when compared to putting a small amount of the same shield on a large transmitter like a cellphone. Remember, the entire phone radiates. Placing a small amount of shielding, even if it is an effective shielding material, only shields that small area at best. Think about this analogy: no light will penetrate a penny as it is a very effective light shield, but it is silly to think that holding a penny up to the sun will put you in darkness.

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.

Of course, scientific seesawing like that doesn’t provide a lot of clarity or confidence for the 90 percent of American adults and roughly 80 percent of teens who report having a cell phone. So how concerned should you be about cell-phone radiation? Consumer Reports’ health and safety experts conducted a thorough review of the research and offer some guidance.

Over time, the number of cell phone calls per day, the length of each call, and the amount of time people use cell phones have increased. Because of changes in cell phone technology and increases in the number of base stations for transmitting wireless signals, the exposure from cell phone use—power output—has changed, mostly lowered, in many regions of the United States (1).