Horiba B-731 LAQUAtwin Compact Potassium Ion Meter
Regular Price $350.00 Special Price $308.00

Only compact meter for a quick measurement of potassium ion using ion selective membrane.Flat sensor technology and 60 years of sensor engineering realizes a reliable and direct measurement of a drop of the sample from 0.3mL. Use sampling sheet (sold separately) to measure down to 0.05mL or more.Unique sensor mechanism realizes direct measurement of solid, viscous, powder samples. No need for a beaker to calibrate or measure. Just drop the standards and sample on the flat sensor, saves you time and minimize wasting your precious sample.This lightweight, pocket-sized meter is suitable for research and industrial applications in diverse fields. Applications include: Soil and sap testing for improved agriculture; food testing* * Detection of ions in water only; electrolytes in oils cannot be measured. Ion measurement can be affected by non-target ions. Functions • Autocalibration function recognizes standards and is user-selectable for either one- or two-point calibrations. • Auto range change • Temperature compensation • IP67 waterproof • Auto hold • Automatic power off (30 minutes)



Measurement principle

Ion electrode method

sample volume

0.3mL or more*1

Measurement range

39 to 3900 ppm(mg/L)(10-3 to 10-1 mol/L)
20 to 2000 kg/10a*2 

Display range

0 to 9900ppm(mg/L)*3

Range and Resolution
(Valid numbers)

①0 to 1.0ppm : 0.1ppm
②0 to 99ppm : 1ppm
③100 to 990ppm : 10ppm
④1000 to 9900ppm : 100ppm




±10% of reading value.*5


Auto range change・Temperature compensation・Waterproof*6Reading locking ・Automatic power off (30 minutes)


Custom (monochrome) Digital LCD


5 to 40˚C, 85% or less in relative humidity  (no condensation)


CR2032 batteries (x2)

Battery life

Approx. 400 hours in continuous use

Main Material

ABS epoxy


164mm × 29mm × 20mm  (excluding projections) / Approx. 50 g (meter only, without batteries)

Accessories included

2 CR2032 batteries/1 Pipette/Instruction manual/Quick manual/Storage case/Standard solution
(150ppm&2000ppm)(14mL)/5 pieces of Sampling sheetB