Nelly's Security Network RJ45 CAT5 CAT5e CAT6 and RG59 Siamese BNC CCTV Continuity Cable Tester Tool Tests continuity and correct cable connector termination for RJ45 and BNC Connections. RJ45 connections are most commonly uses on Network cable (CAT5, CAT5e, CAT6), BNC are most commonly used on RG59 Siamese Cable Includes both sending and receiving units. Receiving units has indicator lights that will light up in proper sequence if termination is correct. If terminiation is incorrect, receiver unit may have lights that wont light up or will skip out of sequence. Requires 9V Batter (not included)