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Klein Tools ET45 Digital AC/DC Voltage Tester 12-240V AC 32-330V DC

SKU CH-4X00-B5NF5

Battery-free digital tester checks 12-240V AC and 32-330V DC with LED indication, IP44 rating, CAT III 350V safety and 9.8-foot drop protection

  • FeaturesTester, CE, Voltage-powered, false
  • Height4.45 L x 1.19 W x 1.05 H inches
  • Width4.45 L x 1.19 W x 1.05 H inches
  • Length4.45 L x 1.19 W x 1.05 H inches
  • Weight1.8 ounces
  • Sports Team1 Piece
  • Tests AC from 12V to 240V across four levels
  • Tests DC from 32V to 330V across four levels
  • Bright LEDs show voltage type and level clearly
  • Battery-free operation powered by applied voltage
  • CATIII 350V safety rating with double insulation

Compact Digital Voltage Tester

The Klein Tools ET45 is a battery-free digital voltage tester designed for electricians and technicians who need to verify AC and DC voltage presence in residential and commercial wiring. It draws operating power directly from the circuit under test, so it is always ready without battery maintenance. The tester covers 12-240V AC and 32-330V DC across four indication levels, with LED illumination and DC polarity detection for clear readings. A built-in pocket clip allows convenient carrying on the job.

Fits Standard Outlets And Tool Bags

Built-in test lead holders on the back space the probes for tamper-resistant US-style outlets, letting you insert the tester directly without loose leads. The compact 4.45 x 1.19 x 1.05 inch body weighs only 1.8 ounces, freeing pocket space and reducing fatigue during extended troubleshooting sessions. An auto-off function conserves the voltage-powered operation when the tester is not actively measuring. IP44 ingress protection and 9.8-foot drop resistance let it survive dust, splashes and jobsite impacts.

Four-Level Indication Up To 240V AC And 330V DC

Bright LEDs show four discrete voltage levels for both AC and DC ranges, giving immediate visual confirmation of approximate magnitude and polarity. The CAT III 350V safety rating with Class 2 double insulation provides protection for measurements on fixed installation wiring. The tester does not supply precise numeric readouts, so it is not suited for calibration tasks or low-voltage electronics work requiring millivolt resolution. Buyers needing continuous data logging or true-RMS accuracy should select a full-featured multimeter instead.

Highlights

  • Tests AC from 12V to 240V across four levels
  • Tests DC from 32V to 330V across four levels
  • Bright LEDs show voltage type and level clearly
  • Battery-free operation powered by applied voltage
  • CATIII 350V safety rating with double insulation

Specifications

BrandaFe Power
FeaturesTester, CE, Voltage-powered, false
Height4.45 L x 1.19 W x 1.05 H inches
Width4.45 L x 1.19 W x 1.05 H inches
Length4.45 L x 1.19 W x 1.05 H inches
Weight1.8 ounces
Sports Team1 Piece
TypeClamp

Questions about this item

What is the highest AC voltage the ET45 can measure before it stops indicating?

The tester indicates up to 240 V AC across four levels, so 240 V is the upper limit for AC measurements.

Does the ET45 generate noticeable heat or noise during continuous all-day testing?

The ET45 is powered by the applied voltage, has no internal battery or fan, and produces no audible noise or measurable heat during extended use.

What must I already have to use the ET45 for voltage testing?

You need access to a live circuit within the 12-240 V AC or 32-330 V DC ranges; the tester draws its operating power directly from the voltage under test.

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