We take cryptocurrency — so the coins you hold can buy real hardware.Pay in crypto, spend it on real hardware. Free insured shipping worldwide over $399. Plain, unbranded boxes, sent from Germany.Free insured shipping over $399. Your rate is locked for 30 minutes once checkout opens.Rate locked 30 minutes. Every item sealed, serial-checked and covered by a 24-month warranty.Sealed, 24-month warranty.

Saved items Sign in
Yellow digital multimeter with LCD screen and red black test leads

Klein Tools

Klein Tools MM420 Digital Multimeter Auto-Ranging TRMS 600V 10A 50MΩ

SKU CH-2WRE-KH50B

Auto-ranging TRMS multimeter measures 600 V AC/DC, 10 A current and 50 MΩ resistance with lead-alert LEDs, backlit display and 6.6 ft drop rating

  • Measures voltage, current and resistance with auto-ranging TRMS accuracy
  • Lead-alert LEDs show correct lead placement for safer testing
  • Backlit LCD gives clear readings in dim conditions
  • Survives a 6.6-foot drop for site durability
  • Includes test leads, thermocouple and batteries ready to use

Versatile Electrical Tester

The Klein Tools MM420 is an auto-ranging TRMS multimeter built for electricians and technicians working in residential, business and light-industrial environments. It measures AC/DC voltage up to 600V, AC/DC current up to 10A and resistance up to 50 MOhms. Additional functions include temperature, capacitance, frequency, duty cycle, diode test and continuity checks.

Lead-Alert Safety and Access

LED indicators on the meter body illuminate to confirm correct test lead placement, reducing connection errors during live measurements. A backlit LCD ensures readability in dim conditions. The unit includes a built-in kickstand, test lead holders and accepts optional magnetic hangers (Cat. Nos. 69445 or 69417) for hands-free operation.

Compatibility and Safety Check

Verify that the CAT III 600V safety rating matches the electrical environment you are testing. The package supplies test leads with CAT III/CAT IV safety caps, a thermocouple with adapter, instructions and 2 x AAA batteries. Ensure the 6.6-Foot (2 m) drop rating suits the physical demands of your work site.

Highlights

  • Measures voltage, current and resistance with auto-ranging TRMS accuracy
  • Lead-alert LEDs show correct lead placement for safer testing
  • Backlit LCD gives clear readings in dim conditions
  • Survives a 6.6-foot drop for site durability
  • Includes test leads, thermocouple and batteries ready to use

Specifications

No published specifications for this item yet.

Questions about this item

How do I verify the MM420 is measuring correctly after setup?

Select a known voltage source; the auto-ranging TRMS display should show the expected AC or DC voltage and the lead-alert LEDs will confirm proper lead placement for the measurement function chosen.

What comes with the MM420 and what must I buy separately?

The box includes test leads with CAT III/CAT IV safety caps, a thermocouple with adapter, 2 AAA batteries and the user manual; an optional magnetic hanger (Cat. Nos. 69445 or 69417) is sold separately for hands-free use.

Which measurement ranges on the MM420 should guide my choice?

Choose this model if you need up to 600 V AC/DC voltage, 10 A AC/DC current, 50 MΩ resistance plus temperature, capacitance, frequency, duty cycle, diode and continuity functions in a meter rated for a 6.6-foot drop.

Also in this aisle

People compared these

Same shelf, same checkout — eight coins and a 30-minute rate lock.