The Megger TDR900 is an advanced instrument capable of measuring cable lengths and finding distance to an open or a short using Time Domain Reflectometry. It offers exceptional features and a range capability normally associated with far more expensive instruments. The measurement range spans from 15 feet (5 m) to 10,000 feet (3 km) with a minimum resolution of 20 inches (50 cm). The TDR900 can be used for any cable consisting of at least two insulated metallic elements, one of which may be the sheath or shield of the cable. The Meter has automatic internal matching networks to allow testing of 25½, 50½, 75½, 100½, 125½, or 150½ cables. (These correspond to power, telephony, CATV, and LAN cables.)