The Cable Tec Continuity Tester is a Go/No Go inspection device. 100% inspection accuracy means the elimination of just one call-back pays for the unit. Used alone the LED unit reads shorts and splitters. The push-on sleeve fitting means quick handling. When used together the LED unit and the beeper unit identify clean lines and assist in isolating problems. The two units also identify lines at MDU lock boxes. The LED and beeper unit each measure 3 1/4 x 2 1/8. Nine volt battery and user instructions are included.