If you need a bit more privacy from the cold calls then you might contemplate getting a CPR V2000 Call Blocker. The device is very small and compact, so you can carry it around. It has a 3 caller display screen which gives you the possibility to see three calls simultaneously. You will need only one blocker per telephone line and it will ensure lifetime support.
You can block the unwanted numbers either by pressing the “block now” button or entering #2 on the extension handset. The call blocker has a 3500 number capacity. Additionally, it is fully line-powered so it does not require an external power source or batteries. You can block any unwanted calls using the number ID.