The CTX200 Pocket CAT from Triplett is a cable tester with connections for RJ45. It can test both Cat 5 and Cat 6 cables to TIA568 specifications with instant pass/fail results. A removable remote makes it possible to test coax cables as well.
The unit can also send tones to trace various kinds of cables including twisted pair, multi-conductor, LAN, unpowered electrical wire, and telephone/alarm. It can test for continuity, opens/shorts, reversals, and split pairs. The CTX200 Pocket Cad includes a 9V battery and a pouch.