Twisted pair testing features: tests for shorts, opens, misfires and reversals; tests ExTab/TIA568A and 568B and 10base-t; shield detection tests shield integrity and tests installed wiring and jumper cables. CAT features: F connector for troubleshooting CAT coaxial installations; tests for opens and shorts; tests cable lengths from 3 to 600 ft. (0.9 to 183 m). Comes complete with 2 x AAA batteries.