About this item 
Automatic blocking features: works well in blocking all robo calls, election calls and telemarketer calls. 
Easy to set up and use: support battery or phone line power. 
Large capacity: block 2000 numbers and area codes, 2000 numbers up to 16 digits. How to install and operate. 
Call record function: record your own outgoing message, any Langage is available, it's a new function. 
Block no cidd: it can block all calls without caller ID (hidden numbers).