$75 - $100

AI223 SX620 pH Pen Tester Kit (±0.01 pH) by Apera

• The smallest pH pen with a reliable testing performance for regular liquid e.g. pools, hydroponics, aquaculture, cooling towers, beverage making, body fluid, etc
• ±0.01 pH accuracy; Automatic 3-point calibration; 0-60°C Automatic Temp. Compensation
• A slim replaceable probe, suitable for test tubes
• Intelligent functions: switch from °F to °C, automatic power-off, pH probe invalidation reminder (remind you to replace the probe for better performance)
• Complete kit: 3 types of premixed calibration solutions (4, 7, 10) and storage solution (3M KCL) all in one portable case

LabSen 335 POM-body pH/Temp. Electrode for Wastewater Treatment by Apera

Crafted with proprietary sensor technologies and premium materials from Switzerland, LabSen 335 pH/temp. Electrode is designed for high-precision pH measurement of wastewater, suspensions, emulsions, slurries, and other dirty liquids. It also works well for general water solutions.

• The combination of open junction and polymer electrolyte eliminates the common issue of junction clogging in dirty liquid testing, ensuring consistent and precise results
• Long-life reference system for stable reference potential and long service life
• The specially formulated blue gel inner electrolyte eliminates the chance of any air bubbles inside the sensor. Just so you don't have to worry about jumping readings out of nowhere
• The built-in temperature sensor enables automatic temperature compensation

PROBONE OnePen Replacement Probe by Bluelab

Unlock the secrets to thriving plants. Maximize the life & accuracy of your Bluelab OnePen™

Features

• Extends the life of your Bluelab OnePen™, minimizing the need for full device replacements
• Quick and simple to replace, reducing downtime and keeping your OnePen™ functioning optimally
• Built to last with a double-junction pH probe and titanium EC electrodes
• Delivers precise pH, Conductivity (EC), and Temperature readings with easy calibration
• Cost-effective, sustainable maintenance
• IP68-certified waterproof and dustproof