<b>This is the original WiFi Router Guard invented and designed by Smart Meter Guard. Be aware of copies. <br><br>The WiFi Router Guard is a custom Faraday cage that blocks about 85% or so of the EMF or RF waves WiFi Routers emit. <br><br>Simple and easy to use. No need to turn off your router and unplug the wires that reset your router. Simply lift the lid of the Router Guard and drop your router in the Router Guard with the wires and cables.<br><br>The Router Guard is made for most small WiFi routers that are SMALLER than 12 x 9 x 3 inches in size. Please measure your router and make sure there at least "1 inch" space for the cables to fit. <br><br> Please measure your WiFi router to make sure it is slightly smaller than 12 x 9 x 3 inches. If your router has antennas the antennas will rotate and fold down. Please rotate and fold down the antennas and then measure your router so make sure it is slightly smaller than the 12 x 9 x 3 inch size of this Router Guard. <br><br>The Router Guard does not fit large routers like the Comcast Xfinity or ATT Uverse routers. If your router is larger than this dimension please see our "Large Router Guard" product. Please view the Router Guard image that shows how your router will fit in the Router Guard and the size you need for your router to fit in the Router Guard. Also, please take into account any base structure that is on your router. Measuring EMF is complicated, make sure you have the correct RF meter. If you decide measure RF, radio frequency, waves please make sure you are measuring in units of micro watts per meter square, uW/m2. <br><br>Measuring RF is complicated. If you are measuring in units of Gauss, mT then you are using the wrong meter and measuring the wrong field. Please please use the Gigahertz Solution HF 35C or the Cornet ED88T Plus RF meters .If you use a TriField meter set it to Radio/Microwave or RF mode. <br><br>Fast Prime like shipping All orders shipped the same or next day by fast 2-Day Priority Mail