... 2690MHz■Typical Radius Range: Up to 30 Meters (depending on the mobile service provider's network condition and background signal ... Reviews:1.With this 4G cell phone jammer, I can get rid of the niose of the 4G mobile ... 2. No matter what other people to choose, I really like this one.3. Have bought one ... really good, the product is ok, better than I thought, actually5. thanks for the good supply, good ...