This cell phone jammer call blocker has worked for me as advertised by the manufacturer since I bought it and installed it 4 weeks ago. For the record, I get my phone service via Mediacom cable company VOIP internet phone service. My digital phone is AT&T Model TL92271 DECT 6.0. I installed the call blocker in series ahead of my AT&T phone per manufacturer instructions. My answering feature on my phone works as before; caller ID info (when provided by incoming caller) is displayed on the phone display; caller ID info (when provided by incoming caller) is also verbally announced by the phone as before ... so all phone features continue without any issues.