Klein Tools in the world of measurement technology

Klein Tools is a renowned brand with a long tradition, known for its power and hand tools that provide professionals with reliable and robust solutions. Their line of measurement equipment, which includes multimeters and clamp meters, is designed for use in demanding conditions where there are frequent falls, mechanical stress, and high safety requirements.

Multimeters measure various electrical quantities such as voltage, current, resistance, frequency, and temperature. Clamp meters allow current to be measured without interrupting the conductors, as the measuring “jaw” is simply placed around the conductor.

We have written this article to help you decide which measurement tool is best suited to meet your requirements. We present some of the best-selling models of multimeters and clamp meters and provide a comparison between them. We paid special attention to important features such as quality construction, fall protection, reliable components, and specific functions such as TRMS, LoZ, or dual display—features that made Klein Tools products stand out.

Below are the key features and differences between the three best-selling models:

• The MM420 model is the basic TRMS version with all standard measurement functions, suitable for everyday use where higher voltages are not required.

• The MM450 is a slim, thinner version, which makes it easier to handle and more compact in design, while still offering all the standard functions. It is ideal when you need a handy multimeter that is easy to carry around, without having to compromise on basic measuring functions.

• The MM720 upgrades functionality with the ability to measure up to 1000 V, a higher resistance measurement range, and the inclusion of a LoZ (Low Impedance) function that helps identify “phantom” voltages and eliminate interference. Due to its higher safety rating (CAT IV / CAT III), this model is more suitable for industrial use, demanding applications, and higher voltages.

To sum up: the MM720 is the “most powerful” of the trio (greater ranges, LoZ function), the MM450 is the most compact, and the MM420 is just right for general use.

Video overview of Klein Tools multimeters: https://youtu.be/pOouef1uqHM?si=j5FzbuHsypP9ZzmA

CL490 – 400A AC/DC Dual-Display Auto-Ranging Digital Clamp Meter

• AC/DC clamp meter with True RMS provides accurate and reliable measurements across various applications
• Dual Display digital clamp meter allows users to see readings in tight space areas
• Measures AC/DC current and NCVT via clamp; AC/DC voltage, resistance, continuity, frequency/duty cycle, DC microamps, diode test and capacitance via test leads; temperature via thermocouple
• Non-contact voltage detection is integrated into the clamp jaw, with audible and visual indicators that intensify as the clamp moves closer to the voltage source
• Withstands drops from 2 m
• Backlit reverse-contrast LCDs for clear data and best view-ability in all environments
• Ergonomic design provides a comfortable grip, with easy dial adjustment using the thumb

CL710 – 600A AC/DC Auto-Ranging TRMS Clamp Meter

• Clamp meter with True RMS provides accurate and reliable measurements across various applications
• Measures AC/DC voltage, AC/DC current, resistance, diode test, continuity, capacitance, and frequency/duty cycle
• Transflective reverse-contrast display provides excellent visibility in both sunlight and dark environments
• Illuminated dial ensures clear visibility and easy reading, even in low-light environments
• Features a low impedance (LoZ) mode to identify and eliminate ghost voltages, preventing false readings and ensuring more accurate measurements
• Non-contact voltage detection is integrated into the clamp jaw, with audible and visual indicators that intensify as the clamp moves closer to the voltage source
• Durable Clamp Meter is rated IP40 for ingress protection and withstands drops up to 2 m

CL900 – Digital Clamp Meter, AC Auto-Range TRMS, Low Impedance (LoZ), 2000 Amp

• Digital Clamp Meter measures 2000A AC/DC, 1000V AC/DC, 60 Milliohm
• Rugged Klein TOUGH METER industrial design stands up to jobsite demands; built to withstand a 2m drop
• Automatically ranging True Root Mean Squared (TRMS) measurement technology for accuracy
• CAT IV 600V, CAT III 1000V, Class 2, double insulation safety rating
• Backlit display for clear visibility in environments with low ambient lighting
• Dedicated mode for capturing Inrush Current
• Non-contact voltage tester integrated into the clamp
• Low impedance (LoZ) mode for identifying and eliminating ghost or stray voltages
• Audible continuity, capacitance, diode test, frequency and duty cycle, min/max feature, data hold capability
• Test leads measure AC/DC voltage, resistance, continuity, frequency, duty-cycle, capacitance and diodes
• Clamp measures AC and DC current
• Powers off automatically after 30 minutes of non-use to conserve battery life
• Low battery indicator and easily accessible battery compartment