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HANNA Iron Low Range Handheld Colorimeter


The HI-746 Iron low range Checker is a simple, accurate and cost effective way to measure low ranges of iron in water.

Designed as a more accurate alternative to chemical test kits, the HI-746 provides quick, accurate results in four easy steps.

HI-746 uses an adaptation of the TPTZ method.

Ideal for:

  • Fresh water aquariums only
  • Water quality
  • Education
  • Industrial
  • Municipal water


Key features:

  • Small palm-sized design
  • Accurate from ± 20 ppb ±5% of reading
  • Dedicated to a single parameter
  • Auto power off after 10 minutes of inactivity
  • Built-in timer for timed reaction readings


Order Information

The HI-746 Iron low range Checker is supplied with sample cuvettes with caps (2), Iron low range reagent starter kit x 25 (re-ordering information HI-746-25 x 25 tests), glass cylinders with rubber cap (2), battery, instructions and quick start guide.

Also available: HI-746-11 Calibration set

Also available: HI-721 Iron High Range (ppm)

Four steps. One click. Instant Readout.

1. ‘Zero’ the Checker®HC with your vial & water sample inside

2. Take the vial out and add your reagent

3. Place your vial into your Checker®HC

4. Press the button and read the results

Battery powered – Allows use away from a power source. Batteries are included with all battery operated products.

Use HI-746-25 Reagents for HI-746 Iron LR handheld Colorimeter - Checker®HC x 25 tests.

Use HI-746-11 Calibration Check Set for HI-746 Iron LR handheld Colorimeter - Checker®HC.


Specifications list


Range 0 - 999 ppb
Resolution 1 ppb
Accuracy (@ 25°C) ± 20 ppb ± 5% of reading
Light Source LED @ 575 nm
Light Detector Silicon photocell
Environment 0 to 50°C (32 to 122°F); RH max 95% non-condensing
Battery Type (1) 1.5V AAA
Auto-off After 10 minutes of non-use
Dimensions 81.5 x 61 x 37.5 mm (3.2 x 2.4 x 1.5")
Weight 64 g (2.25 oz.)
Method adaptation of the TPTZ method