simpson 8455 Line Loop Tester 

Simpson’s Model 8455 Line Loop tester detectsline shorts, opens and multiple ringers, DC voltages and loopresistance. It can measure DC voltage up to 100 volts and loopresistance to 2 megohms. A front panel “reverse polarity” switchallows changing polarity positions quicker and easier than manuallyswitching test leads when making line checks. This switch isfield-replaceable, enabling your loop tester to be operational atall times without costly shop repairs. The compact durableconstruction of this tester ensures continued accuracy even underthe most rugged field conditions.

• Field Replaceable Switches - Allows operator toget back to the job quickly
  with less downtime. The replacement toggles or push buttons can bekept in
  the truck and replaced on site, keeping the unit in service, atall times.
• Designed for Telecom Applications - Accuratelychecks line shorts, opens
  and multiple ringers.
• Wide Measuring Range - Measures DC voltage0-100V and resistance R x 1,
  R ÷ 10.
• Shorter Testing Time - Polarity toggle switcheliminates manually switching
  test leads when conducting line checks.
• Rugged for Field Use - Durable, compact (5-1/2"x 2-3/8") construction
  makes it portable, easy to store and rugged.
• Accurate, Finer Readings - 0-100 points scalecalibration yields accurate
  readings.

• Specifications DC Voltage: Range: 100V Sensitivity: Model 8455, 1K _ per volt Model 8455 A, 3333 _ per volt Isolation: 100V DC max. circuit to earth ground Overload Protection: 10mA/250V fuse on all ranges Temperature Coefficient: (57OF to 97OF): ±2% F.S. (VDC) BatteryType: (1) Eveready #455 (45V); Catalog Number 06-113313 Physical: Dimensions: 5.5" (H) x 3.6" (W) x 2.4” (D), (14 x 9 x 6 cm.) Weight: 1 lb. (0.5 Kg.) Specifications subject to change without notice.