AT&T BL3112-4 Expandable 4-Handset Cordless Phone with Answering System, Bluetooth and Smart Call Blocker lets you connect your cellphones and headset with Bluetooth. Experience the seamless landline and cellular call capabilities. Screen and block unknown calls and robocalls on your landline with Smart call blocker and store up to 1,000 names and numbers to the block list. Save up to 1,000 contacts to the directory. Join an landline call with 4 cordless handsets and enjoy superior sound quality. Quick access with the convenience of phonebook, caller ID and call waiting, ensuring you stay in touch with loved ones.