This is the device that blocks nuisance calls and prevents your phone from even ringing. It connects to any landline and is pre-installed with a database of numbers of the most notorious telemarketers and spam callers. If a nuisance caller not on the list gets through, the device has a red “Block Now” button that automatically ends the call and adds the number to its database of blocked callers. It has a 3" display, stores additional numbers, and lets you edit the list in the event of an accidental block. Requires caller ID subscription.