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Klein Tools MM320KIT Digital Multimeter Electrical Test Kit, Non-Contact Voltage Tester, Receptacle Tester, Carrying Case and Batteries

Klein Tools MM320KIT Digital Multimeter Electrical Test Kit

Bottom line: The Klein Tools MM320KIT Digital Multimeter Electrical Test Kit ($54.99 on Amazon as of 2026-10-21 10:18 UTC): Four testers in one kit: MM320 meter, NCVT-3P, ET45, RT210; main trade-off: MM320 tops out at 10A DC current, short for high-draw circuit work.

$54.99

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By , Founder & Editor-in-Chief · Listing data updated

Mike Perry — Hardware researcher since 2014. For PC and retro-hardware cleaning and maintenance tools, synthesises manufacturer documentation, community compatibility lists and marketplace listings rather than first-hand lab testing. Core beat: GPU performance across gaming, rendering, and local-LLM inference.

*Price sourced from Amazon.com. Last updated 2026-10-21. Price and availability subject to change.

Pros & Cons

Pros

  • ✓ Four testers in one kit: MM320 meter, NCVT-3P, ET45, RT210
  • ✓ MM320 reads to 600V AC/DC, 10A DC current, and 2 ohm resistance
  • ✓ NCVT-3P covers dual ranges, 12-1000V AC and 70-1000V AC
  • ✓ RT210 catches open ground, reverse polarity, open hot/neutral, hot-ground swap

Cons

  • ✗ MM320 tops out at 10A DC current, short for high-draw circuit work
  • ✗ ET45 stops at 240V AC, so it will not cover 480V commercial panels
  • ✗ RT210 only reads standard and GFCI receptacles, not AFCI-specific faults
  • ✗ Four separate tools plus leads means four battery types to keep stocked

Manufacturer description

The Klein Tools MM320KIT bundles four electrical testers into one padded case, so you can move from a service panel to a bedroom outlet without swapping kits. The MM320 digital multimeter reads up to 600V AC/DC, 10A DC current, and 2 ohm resistance, and it also checks batteries, diodes, and continuity. Alongside it, the NCVT-3P non-contact voltage tester covers dual ranges of 12 to 1000V AC and 70 to 1000V AC, with a built-in flashlight that works independently of voltage detection when you are reaching into a dim crawlspace. The ET45 voltage tester handles 28V to 240V AC and 32V to 330V DC…

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SpecPicks Verdict

SpecPicks scored Klein Tools MM320KIT Digital Multimeter Electrical Test Kit using a rating × review-volume × price-fit model applied to published specs and reviews across the tools & maintenance category. Compare with similarly-priced alternatives in the tools & maintenance category before committing. Judge it on the specification table and the price rather than on sentiment: check the figures that decide your use case, then put it side-by-side with two or three close alternatives in the Compare tool before clicking through.

Common buyer scenarios for tools & maintenance: PC towers accumulate significant dust in 3–6 months, so cleaning frequency drives cordless vs. canned-air tradeoff decisions. Match the device's RPM or CFM rating to your case size, and confirm battery runtime covers a full tower cleaning before ordering. Prices and stock are set by the retailer and may have moved since this page was last updated.

Frequently Asked Questions

What tools come in the Klein Tools MM320KIT?

Four: the MM320 digital multimeter, the NCVT-3P non-contact voltage tester with flashlight, the ET45 voltage tester, and the RT210 GFCI receptacle tester, plus a padded storage pouch and all required batteries.

How much voltage can the MM320 multimeter measure?

Up to 600V AC/DC. It also measures 10A DC current and 2 ohm resistance, and tests batteries, diodes, and continuity.

Will the non-contact tester detect low-voltage wiring?

Yes. The NCVT-3P is dual-range: it detects 12 to 1000V AC in low-voltage mode and 70 to 1000V AC in standard mode, so doorbell and thermostat wiring is in range.

Can it test tamper-resistant outlets?

Yes. The ET45 has a built-in test lead holder on the back with two positions that space the leads correctly for tamper-resistant outlets, and it doubles as lead storage.

What wiring faults does the RT210 receptacle tester find?

It flags the most common faults in standard and GFCI receptacles: open ground, reverse polarity, open hot, open neutral, and hot/ground reversed.

Key Features

  • VERSATILE MEASUREMENTS: Digital Multimeter accurately measures up to 600V AC/DC voltage, 10A DC current, and 2 ohm resistance, offering precise readings for various electrical tasks
  • EXTENSIVE FUNCTIONALITY: In addition to voltage, current, and resistance, the meter tests batteries, diodes, and continuity, providing comprehensive testing capabilities in one device
  • DUAL-RANGE VOLTAGE DETECTION: Voltage Tester NCVT3P detects from 12 to 1000V AC or 70 to 1000V AC, accommodating a wide range of low-voltage and standard voltage applications
  • BUILT-IN FLASHLIGHT: The NCVT3P features a bright flashlight that illuminates the work area, offering convenient visibility and independent use from the voltage detection function
  • ACCURATE AND WIDE-RANGE TESTING: ET45 tests AC voltages from 28V to 240V AC and DC voltages from 32V to 330V, covering commonly used residential voltages for reliable testing
  • CONVENIENT TEST LEAD HOLDER: The ET45 comes with a built-in test lead holder on the back, providing two positions for correctly spacing the leads for testing tamper-resistant outlets or convenient storage

Full Specifications

BrandKLEIN TOOLS
ColorMulti
ModelMM320KIT
StyleMultimeter and Receptacle Tester Kit
Style NameMultimeter and Receptacle Tester Kit
Unit Count1 Count
Part NumberMM320KIT
Power SourceBattery Powered
Item Type NameMultimeters
Item Dimensions12.4 x 7.91 x 2.24 inches
Number of Items1
Measurement TypeMultimeter
Specification MetCE, ETL, NIST, RoHS, UL
Included ComponentsMM320 Manual Ranging Digital Multimeter, ET45 AC/DC Voltage Tester
Warranty DescriptionPlease refer to attached warranty document for information
DUAL-RANGE VOLTAGE DETECTIONVoltage Tester NCVT3P detects from 12 to 1000V AC or 70 to 1000V AC, accommodating a wide range of low-voltage and standard voltage applications
ACCURATE AND WIDE-RANGE TESTINGET45 tests AC voltages from 28V to 240V AC and DC voltages from 32V to 330V, covering commonly used residential voltages for reliable testing
Global Trade Identification Number00092644693403
Full listing titleKlein Tools MM320KIT Digital Multimeter Electrical Test Kit, Non-Contact Voltage Tester, Receptacle Tester, Carrying Case and Batteries

Ready to buy?

Klein Tools MM320KIT Digital Multimeter Electrical Test Kit, Non-Contact Voltage Tester, Receptacle Tester, Carrying Case and Batteries is listed on Amazon. Price, availability, shipping and returns are set by Amazon and its sellers — check the listing for current terms. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.

Buy on Amazon — $54.99

*Price sourced from Amazon.com. Last updated 2026-10-21. Price and availability subject to change.

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Klein Tools MM320KIT Digital Multimeter Electrical Test Kit, Non-Contact Voltage Tester, Receptacle Tester, Carrying Case and Batteries
$54.99
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