SIMPSON Teledata 8455 Line Loop Ohm Tester/Meter Test Leads Case USA Polarity toggle switch eliminates manually switching test leads when conducting line checks Durable, compact (5-1/2" x 2-3/8") construction makes it portable, easy to store and rugged Accurate, Finer Readings - 0-100 points scale calibration yields accurate readings Allows operator to get back to the job quickly with less downtime. The replacement toggles or push buttons can be kept in the truck and replaced on site, keeping the unit in service, at all times Accurately checks line shorts, opens and multiple ringers Measures DC voltage 0-100V and resistance R x 1, R 10