Klein Tools MM400 is an auto-ranging multimeter that measures AC/DC voltage, AC/DC current, and resistance. It can also measure temperature, capacitance, frequency, duty-cycle, and test diodes and continuity. Klein Tools Test and Measurement product line was exclusively designed from the ground up by electricians for electricians. Years of field research, combined with extensive input from electricians across America, inspired the development of meters and electrical testers loaded with innovative, time-saving features.
- Measures up to 600V AC/DC voltage, 10A AC/DC current and 40 MO resistance
- Measures temperature, capacitance, frequency, duty-cycle, and test diodes and continuity
- CAT III 600V safety rating
- Built to withstand a 3.3' (1 m) drop and withstand daily wear and tear on the job site
- Low battery indicator and easily accessible battery compartment
- For use in basic and controlled electromagnetic environments such as residential, business and light-industrial locations
- Includes test leads, thermocouple with adapter and batteries
- Weight: 1.00 LBS
Height6" (152.4 mm)
Safety RatingCAT III 600V
Width3-1/6" (77.8 mm)
Included AccessoriesTest Leads, Batteries and Thermocouple
Batteries2 x AAA
Drop Protection3.3 ft (1 m)
Depth1-25/32" (45.2 mm)
AC Voltage600V
Diode TestYes
Ohms (Resistance)40MO
DC MicroampsYes
DC MillivoltsYes
Max/MinYes
Auto-Power OffYes
Capacitance Test200F
Magnetic MountAvailable as Accessory
DC Current10A
AC Current10A
Auto RangingYes
Frequency/Duty Cycle1Hz - 50 KHz
LCD Display Count4000
BacklightYes
Range HoldYes
Data HoldYes
DC MilliampsYes
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- Weight: 1.00 LBS
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Klein MM400 Digital Multimeter, Auto-Ranging, 600V How would you rate this product?
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Jocelyn D. Verified Customer 
03-12-25 - canada
Peter K. Verified Customer 03-10-25 - canada
David L. Verified Customer 03-09-25 - united states
