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Are you struggling to obtain precise and reliable water analysis readings in your lab?

The Ohaus Starter Pen Meter ST20D is here to solve your problem. Tailored for discerning professionals, this compact device from Liberty Scales offers unparalleled precision in measuring dissolved oxygen, ensuring that your lab results are both accurate and dependable. Designed specifically for the rigorous demands of modern laboratories, the ST20D facilitates rapid and accurate water analysis, making it an indispensable tool for any setting.

Key Benefits:

  • High Precision Measurements: Enjoy readings with an accuracy of ±0.5 °C across a range of 0.0 – 19.9 mg/L, ensuring that your laboratory instruments deliver exact results every time.
  • Versatile Applications: Capable of measuring pH, oxidation-reduction potential (ORP), conductivity, dissolved oxygen (DO), salinity, and total dissolved solids (TDS), this meter is a versatile addition to your lab equipment.
  • Durable and Reliable: The rugged ABS housing and waterproof design (IP67 rated) protect the meter against harsh conditions, making it suitable for both field and laboratory use.
  • User-Friendly Design: Features like easily replaceable electrodes and an automatic shut-off ensure straightforward operation and enhanced longevity.
  • Portable Convenience: Compact and lightweight, equipped with a wrist strap to prevent accidental drops, the ST20D is designed for on-the-go measurements without the hassle.
  • 5-Year Warranty: Enjoy peace of mind and long-term reliability with a comprehensive 5-year warranty on your investment.

Imagine a day in your laboratory where every measurement is quick, easy, and accurate. With the Ohaus Starter Pen Meter ST20D, you'll boost the efficiency of your daily tasks and experience the peace of mind that comes with reliable, consistent results. This tool will quickly become a valued partner in your quest for precision, providing you with confidence in every reading. Equip your lab with this essential instrument and watch your productivity—and accuracy—soar.

Reach out to our dedicated team for further information and personalized assistance. Call us at (661) 888-1919 or email us at We're here to help you every step of the way!


  • Meter Type: Dissolved Oxygen

  • Measurement Range: 0.0 – 19.9 mg/L

  • Accuracy: ±0.5 °C

  • Measurement Resolution: 0.1 mg/L

  • Display: LCD

  • ATC: Yes

  • Temperature compensation: Automatic

  • Accuracy ± (Temperature): 0.5 °C

  • Automatic Shutdown: Yes, After 6 minutes of non-use

  • Battery Life: 100 Hours with Disposable Batteries

  • Calibration: 1 Point

  • Dimensions: 1.5 in x 7.28 in x 1.77 in (38 mm x 185 mm x 45 mm) (LxHxW)

  • Net Weight: 3.88 oz (110 g)

  • Number of Buttons: 3

  • Power: 4 AG13 Batteries (Included)

  • Protection Rating: IP67

  • Temperature Display: Yes

  • Temperature Range: 0 °C – 99 °C

  • Temperature Sensor: 50 KΩ NTC

  • Working Environment: 41°F – 104°F, 80% RH, Non-condensing (5°C – 40°C, 80% RH, Non-condensing)

  • Wrist Strap: Yes
  • Free Shipping: Available across 48 continental USA. Extra charges may apply for residential, farm, or rural areas.
  • Express Shipping: Overnight and faster shipping options available at additional costs. Quotes obtainable via email.
  • Delivery Time: Typically 5 to 7 business days, varying by location and external conditions.
  • Tracking Information: Provided via email upon shipment. Accessible through account login. Additional information available upon request.
  • Return Policy: 15-day return period for unused, original condition products. A 25% restocking fee applies. Buyer covers original and return shipping costs.
  • Customer Support: Contact at (661) 888-1919 or for queries or concerns about shipping.