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Klein Tools ET40 is an Electronic AC/DC Voltage Tester. It features indicators for positive and negative DC polarity, and tests DC voltages as low as 1.5V. It tests AC voltages 12-240VAC. Excellent for checking, verifying or troubleshooting common residential electrical wiring in electrical outlets, light fixtures, doorbells and more. It operates on 2 x AAA batteries.

Product Features
  • Voltage Tester for AC voltages from 12V to 240V AC at four useful levels aligned with commonly used residential voltages
  • Tests DC voltages from 1.5V to greater than 17 to 24V at four useful levels aligned with commonly used DC voltages
  • Bright LEDs illuminate to indicate the type and level of voltage detected
  • Built to withstand a 9.9 ft. (3 m) drop
  • Indicates polarity when measuring DC voltages
  • Powers off automatically after approximately 2 minutes of non-use to conserve battery life
  • CATIII 250V, Class 2, Double insulation
  • Ingress protection IP41 dust and water resistant
  • Built-in test lead holders on sides of tester
  • Low battery indicator with easily accessible battery compartment
  • Pocket clip secures tester to pocket for reliable everyday carrying
  • Uses 2 x AAA batteries (included)
  • Identifies and distinguishes between AC or DC voltage

Product Specifications
  • Application: Measures AC/DC voltage
  • Special Features: DC Polarity Indicators for DC Positive, DC Negative, and Both Illuminated for AC. Tests Low DC Voltage to 1.5V. Built in Test Lead Holders on Sides of Tester.
  • Material: Plastic Housing, PCB with Electronic Components
  • Batteries: 2 x AAA
  • Drop Protection: 9.9' (3.0 m)
  • Display: Analog LED
  • Control Type: ON/Off Switch for Power ON/OFF
  • Voltage: AC Level Indicators: 12V, 24V 120V, 240V and DC Indicators:1.5V, 9V, 12V, >17-24V
  • Frequency: 50/60 Hz
  • Ingress Protection: IP41
  • Pollution Degree: 2
  • Tests Continuity: No
  • Integral Lead Storage: Yes
  • Interchangeable Leads: No
  • Lead Length: 9'' (228.6 mm)
  • Standard: CATIII 250V, CE
  • Case Included: No
  • Included: Tester, User Manual, and 2 x AAA Batteries
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Manuals (2)
Batteries Included:


Battery Type:


Product Type:

Voltage Tester


LCD Display

Max Voltage:









60 Hz


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