Call Blocker Model CT-CID803 (Versions 1, 2.0, 2.2, N2 & 5.0)Do I need to purchase a second T-Lock Call Blocker if I have 2 phone lines and a 2-line phone?Do I need to purchase a second T-Lock Call Blocker if I have 2 phone lines and a 2-line phone?Yes, you will need a T-Lock Call Blocker per phone line or phone number.