The HORIBA LAQUAtwin pH pocket meter puts a genuine laboratory-grade pH measurement in your shirt pocket. Its patented flat sensor reads a sample as small as a single drop — roughly 0.1 mL — so you can measure pH directly on a leaf, in a soil slurry, on a moist surface, or in a sample far too small for a conventional probe.

The meter is fully waterproof (IP67), calibrates automatically at the touch of one button, and the sensor unit is user-replaceable. When the sensor eventually wears out you swap the sensor rather than replacing the instrument, which keeps long-term running costs low. Each meter ships ready to use with standard solutions, batteries, a dropper and a storage case.

Choose your model

• LAQUAtwin pH-11 (part no. 3999960122) — pH and mV, accuracy ±0.1 pH, 2-point calibration. The economical choice for routine pass/fail checks.
• LAQUAtwin pH-22 (part no. 3999960123) — pH and mV, accuracy ±0.01 pH, 3-point calibration. Ten times the resolution of the pH-11.
• LAQUAtwin pH-33 (part no. 3999960124) — pH, mV and temperature, accuracy ±0.01 pH, 5-point calibration. Best accuracy across a wide pH span, with temperature displayed alongside the reading.

Why the flat sensor matters

A conventional pH probe needs enough sample depth to submerge the glass bulb and reference junction. The LAQUAtwin's flat sensor sits on the surface, so a drop is enough. It is also easy to rinse and wipe clean, and it will not break like a glass bulb — a real advantage in the field and in teaching labs.

Applications

• Soil pH testing from a small slurry or extract, directly at the sample point
• Agriculture and horticulture: nutrient solutions, hydroponics, sap and leaf-surface testing
• Food and beverage QC on small or viscous samples
• Environmental spot checks on surface water, runoff and stormwater
• Boiler, cooling tower and process water monitoring
• Classroom and teaching laboratories where breakage is a concern
• Aquarium, pool and spa water checks

Documentation

• LAQUAtwin pocket meter brochure and specifications (PDF)

Parts & accessories

Replacement S010 pH sensors, pH 4 and pH 7 standard solution sets, sampling sheets and the 6-meter carrying case are all stocked — see the Horiba Parts & Accessories collection.

Browse all HORIBA instruments.