MI406 Colorimeter


The MI406 PRO Photometer features manual zero point calibration and fast operation in a rugged design.

The PRO Photometer is ideal for users in environmental, food, water treatment and lab applications. This meter is also ideal for educators that want their students to learn the basics of water quality analysis to apply in the real world.

The PRO Photometer offers:


The MI406 microprocessor delivers fast results with accuracy of ±0.06 mg/L @ 1.50 mg/L  and is repeatable.

Easy to use and tough

This rugged meter is designed to take knocks. It's low maintenance design paired with easy to use reagents makes the MI406 ideal for everyone from educators and aquaculture, aquariums, environmental professionals to water treatment and food processing.

Lab grade. Easy to use. High performance.


  • Fast easy to read results with large digital LCD readout.
  • Accurate to ±0.06 mg/L @ 1.50 mg/L and a range 0.00 to 5.00 mg/L of (Cl2 Free).
  • Lightweight and portable.
  • Easy measurement: just mix the reagent in the sample, gently shake, insert the cuvette, zero the meter then press read.
  • Simple easy reagent packets or liquid bottles.
  • Easy 1-2-3 instruction steps.
  • Auto shut off after 10 minutes of non-use, 9 volt (battery included).
  • Adaptation of The Nessler Method.


MI406 has a built in timer that ensures appropriate reaction time is used for the chemical reaction.  At the end of the timer, the meter will automatically take the reading. This feature ensures consistency across multiple users.


The MI406 has a built in indexing indent on the meter - The meter has an indent that allows for a lock and key fit with the cuvette cap.  This ensures that the cuvette is indexed consistently (same position) in order to maintain the same path length for accurate results.


The MI406 has built in error messaging display alerts.  This helps the user ensure no mistakes are made in the testing process.  Messages include no cap, over range and under range, light source errors and zero cal error to ensure the user has the most accurate error free readings.


The MI406 has a simple to use zero point calibration.  Simply insert the unreacted sample cuvette into the chamber, index the cuvette and press the zero button.  Your calibration is complete.

Technical Specifications

Free Chlorine Photometer, Range: 0.00 to 5.00 mg/L of (Cl2 Free)

Resolution: 0.01 mg/L (0.00 to 3.50 mg/L)

Resolution: 0.10 mg/L (above 3.50 mg/L)

Accuracy ± 0.06 mg/L @ 1.50 mg/L

Method: adaptation of USEPA method 330.5 & Standard Method 4500-Cl G

Light Source: Tungsten Lamp

Light Detector: Silicon photocell and 525 nm narrow band interference filter

Operating Environment: 0 to 50 C 32 to 122 F / Max. RH 100%

Battery Type: 1 X 9V (included)

Auto-off: after 10 minutes of non-use

Meter Dimensions / Weight: 7.5" x 4.1" x 2" / 0.84 lbs.

Packaging Dimensions / Weight: 12" x 11" x 4.5" / 2.7 lbs.

Meter Dimensions / Weight: 191 mm x 107 mm x 51 mm / 1.22 kg.

Packaging Dimensions / Weight: 305 mm x 280 mm x 115 mm / 1.5 kg.

Glass Cuvettes: MI0001 ( 2 x included)

Contact us

If you have any questions or require further information, please do not hesitate to email us at [email protected], call us on +44 (0)113 286 4536 or submit a contact form.