EarthCalm's Mirror Resonance Technology (MRT) has been researched, tested, and steadily improved for over 30 years. Our EMF protection devices have become well known over the decades for their strength and effectiveness. Customers consistently report back to us about their relief from various EMF-related ailments, such as tinnitus, chronic headaches, sleep disorders, depression, anxiety, the list goes on and on! We encourage you to try EarthCalm products and experience how the technology works for you. If you're not satisfied for any reason, all of our products come with a 1-Year Warranty and a 90-Day Money-Back Guarantee!