So far the cell phone jammer is working great. Once the call blocker was set up Incoming nuisance calls immediately declined by about two thirds. Apparently the 5K prerecorded blocked numbers that come with the Call Blocker did that job. Usually I would get 4 telemarketing calls on Monday mornings by noon. None were received the first Monday after installation of the Call Blocker. Those were calls I could not block with the call blocker that came with my landline set. This block works great for all the calls requesting political contributions with no number showing. Also included with the Blocker was an app to block calls on my cell if needed. The fact that the phone doesn't ring at all with this blocker is a blessing. So far the jamming device is my new best friend.