The Klein Tools Cable Length Meter is a portable Time Domain Reflectometry (TDR) cable length tester. It measures cable length, calibrates Velocity of Propagation (VoP) values, finds distance to faults in cables, and provides built-in tone generation for cable tracing. This tester provides accurate cable length measurement for a wide variety of cable types at an affordable price. Includes test leads and a carrying case. Features: Cable length meter measures length of electrical, data, two-wire and Romex® cables up to 3000 feet (914 m); TDR technology measures Distance-to-Fault, Open or Short, on terminated or unterminated cable; Programmed with Velocity of Propagation (VoP) values for Coax, Data, Romex® and other multiwire cables for accurate length measurement within +/-(2-Percent plus 3-Foot/0.9 m) accuracy; Stores custom cable VoP values for consistently accurate results and time savings; Simple interface with full color, interactive LCD; Tones unenergized, open-ended wires for wire tracing (requires Analog Probe (Cat. No. VDV500-123, sold separately); Coax-BNC or high quality alligator clips for quick, easy connection to test most cable types; RJ45 jack for accurate length measurement of terminated data cables; Measurements can be switched between and metric and imperial units; Includes padded carrying case and leads; Velocity of Propagation Range: 20 to 99.9% - Warnings: The Cable Length Meter should NOT be used on energized cabling systems.; Internal components of the Cable Length Meter are protected up to 30V peak AC or DC. Connecting the meter to voltages above this range may pose a safety hazard to the user and the meter. - Replaced By Products: 770910