Klein Tools MM720 Digital Multimeter - Accurate TRMS Measurements

In this review the Klein Tools MM720 proves to be a solid, professional-grade multimeter for electricians, HVAC techs, maintenance staff and serious DIYers. The single biggest reason to buy is its combination of True RMS accuracy with a low impedance mode that eliminates ghost voltages, making readings more reliable on complex or energized systems. It ships as a complete kit and feels built to last, so users who need dependable measurements across voltage, current and resistance will find real value here.

Key Features

• High voltage and current range: Measures up to 1000V AC/DC and 10A AC/DC so it handles heavy-duty electrical work without swapping meters.
• TRMS accuracy: True Root Mean Squared measurement provides more accurate readings on non-sinusoidal and noisy signals than basic meters.
• Low impedance mode (LoZ): LoZ helps identify and eliminate ghost or stray voltages so troubleshooting is faster and more reliable.
• Durable construction: CAT IV 600V rating, IP42 and a 6.6-ft (2 m) drop resistance make it suitable for industrial and field use.
• Readability and convenience: A reverse-contrast LCD with automatic optical sensing improves visibility in bright or dim conditions and test lead holders plus a kickstand simplify hands-free work.
• Complete kit: Includes carrying case, test leads with safety caps, thermocouple and batteries so it is ready to use out of the box.

Who It's For

The MM720 is aimed at professional technicians and serious hobbyists who need a dependable, rugged multimeter that covers a wide range of measurements including voltage to 1000V, current to 10A and up to 60 MOhms resistance. Its low impedance mode is particularly useful for electricians who must distinguish real voltage from ghost readings on multi-wire systems.

Those who primarily need ultra-compact meters for simple household tasks or extreme-display clarity in every situation might consider models focused specifically on ergonomics or larger displays. However, for field service, HVAC, maintenance and industrial jobs the MM720 strikes a strong balance of features and durability.

Pros & Cons

Pros

• Rugged design and safety ratings (CAT IV 600V) suitable for professional environments.
• Accurate TRMS readings and a practical LoZ mode that reduces misleading ghost voltages.
• Complete, ready-to-use package including thermocouple and test leads with safety caps.
• Convenient extras like test lead holders, kickstand and optional magnetic hanger for hands-free work.

Cons

• Display readability receives mixed feedback - the reverse-contrast LCD helps, but some users may find it less clear in normal lighting than expected.
• Not the smallest meter for pocket carry compared with basic compact testers.

Specifications

Our Verdict

The Klein Tools MM720 is a rugged, well-rounded multimeter that delivers accurate TRMS readings and practical features like LoZ for troubleshooting ghost voltages. It offers professional safety ratings and a complete accessory kit, making it a strong value for technicians and maintenance pros who need a reliable, durable meter on the job.

Frequently Asked Questions

Does this meter handle professional voltage ranges?
Yes, the MM720 measures up to 1000V AC/DC and carries a CAT IV 600V safety rating for professional use.

Can it detect ghost voltages?
Yes, the built-in Low Impedance (LoZ) mode is designed to identify and eliminate ghost or stray voltages while testing.

What is included in the box?
The package includes a carrying case, test leads with safety caps, a thermocouple, instructions and 2 x AAA batteries.