Enf510 Call Blocker For Landline Phones, Answering Machine, And, Family Use. ? 2 years warranty , If you have any questions, PLEASE CONTACT CUSTOMER SERVICE, we will reply within 16 hours and solve the problem for you. ? Lifetime technical support. ? Blocking the changing number starting with a fixed number, such as 443, 800, 855, 866, 999, 7324, 33626 etc . ? Blocking International, Private/WITHHELD, VOIP/Out of Area callers. ? Preloaded with 4000+ most complained caller numbers . And 3000+ manual blocking capacity for building your own database . Touch the BLOCK button on the CALL BLOCKER (OR press "#" then "6" on the phone) - BLOCK Scam / spam and all unwanted calls . ? ?FAMILY LIST? function --- You can add important contacts to the FAMILY LIST to avoid being blocked by mistakes . ? No main power required, just plug in the phone line to use . ? NOTE: enf510 only displays the caller's number, not show caller's name AND CALLER ID SERVICE IS REQUIRED from your landline provider for ENF510 to work . Enf510 CALL BLOCKER does NOT support digital phones.