Visit for Information on the Corona-virus disease (COVID-19) Pandemic.
If you do not understand these 3 words, google them: symptom, symptomatic and asymptomatic. Some of us were ignorant at Clarkson but not anymore.

How many young people under the age of 18 have died while having the Corona Virus in the state of California in the USA with a population of 39.5 million?
CDPH shows 104 as of May 9, 2023. This is 0.0002% of the California population. Have a health problem or over 80, yes it is dangerous but so is the Flu and Pneumonia.
Sweden with 10 million people never had any mask mandate and had the same results as the state of California! - - References: CDPH , Flu and Sweden

Browse by Manufacturer
Browse Categories

Solution Graphics
Search our store

Starter ST20M-B Multi Parameter Pen Meter

<< Previous in Ohaus pH Meters & Testers Next in Ohaus pH Meters & Testers >>
List Price: $162.00
Clarkson Price: $137.70
You Save: $24.30 (15 %)
Clarkson Catalog Number: 30393199
Manufacturer: Ohaus
Supplier Catalog Number: 30393199
Manufacturer Direct Shipment. MAP item, email us for the best price.
free shipping
Ohaus ST20M-B, Ohaus 30393199, Ohaus ST20M-C, Ohaus 30393200
Ohaus ST20M-B, Ohaus 30393199, Ohaus ST20M-C, Ohaus 30393200Ohaus PH20
Clarkson 30393199
Starter ST20M-B Multi Parameter Pen Meter
Ohaus 30393199
For over a century, OHAUS has perfected the art of measurement through our line of weighing products. Taking a similar approach to our weighing equipment, OHAUS now delivers a line of pen meters that are durable, practical and affordable. Starter pen meters—the portable solution for on-the-go measurement of pH, oxidation-reduction potential (ORP), conductivity, salinity, total dissolved solids (TDS) and dissolved oxygen (DO). Starter pen meters are the economical option when you are simply looking for accurate measurements with no restrictions

Standard Features Include:
  • Simple Operation in a Slim and Portable Design: Starter pen meters provide what should be expected of a small pen meter. Simple, fast, straightforward, no-frills yet highly accurate operation time and time again.
  • Durably Constructed to Withstand Wear and Tear Resulting from Repetitive Use: With durable plastic housing, a protective cap that safeguards the sensor, and an automatic shutdown feature to preserve battery life, the Starter pen meters can endure consistent use in rugged environments.
  • •Waterproof Housing Protects the Meters in their Working Environment: Equipped with a wrist strap that helps to prevent unintentional dropping, Starter pen meters are constructed with an IP67 waterproof design that can prevent water damage when accidentally dropped into liquid.
Convenient pH Testing:

Two models with varying resolution and accuracy; the ST10 and ST20 offer a convenient way to measure pH, or the relative acidity or alkalinity of a sample at a given temperature. The pH pen meters can be operated with just one hand, freeing up your other hand to handle samples.
  • pH Meters: ST20 , ST10
Portable ORP Measurement:

ST10R and ST20R can provide measurement of ORP virtually anywhere the need for measurement of the availability of electrons in a liquid exist. Both models provide almost instantaneous results and the ST20R offers the ability to hold the reading right on the display to provide additional time for data logging.
  • ORP Meters ST20R, ST10R
Productive Conductivity Meters:

Starter pen meters are the choice for basic testing needs of the total ionic concentration within a solution. With six models that can measure within three different conductivity ranges, there is a Starter conductivity meter for every application that requires portable operation and quick results.
  • Conductivity Meters: ST20C-C, ST20C-B, ST20C-A, ST10C-C , ST10C-B, ST10C-A
Simple Salinity Measurement:

Starter pen meters combine all of the most useful features for measuring salinity in a liquid medium. With the combination of quality construction and sturdy design, Starter pen meters will provide durable operation in even the toughest environments.
  • Salinity Meters: ST20S, ST10S
Multi Parameter Meter:

The OHAUS ST20M is a multi parameter pen meter that directly measures pH, conductivity and temperature, as well as provides conversion measurements for TDS and Salinity. These fully waterproof pen meters combine measurement capabilities of two testers in one convenient pocket-sized unit. Great for water, laboratory or plant use, the ST20M features a singlejunction pH electrode and a pin-style conductivity probe for longer usage and durability. The replaceable electrode module saves you money by reusing the meter body. Advanced features include autoshutoff, low-battery indicator, and simple and easy calibration.
  • Measures 5 parameters including pH, Conductivity, TDS, Salinity, and Temperature
  • Waterproof rated to IP67
  • Automatic Temperature Compensation
  • Auto shutoff with low battery indicator
  • ST20M meter includes electrode, protective sensor cap, four AG13 1.5V batteries, and wrist strap.
  • Multi Parameter Meters: ST20M-B, ST20M-C
Simple and Fast Dissolved Oxygen (DO) Measurement:

The perfect DO meter for every application that requires portable operation and quick results. With IP67 waterproof design and automatic shutdown feature that preserves battery life, the Starter DO meter can endure consistent use in rugged environments.
  • DO Meter: ST20D
Complete TDS Meters:

When you need reliable and accurate measurement of TDS, the Starter pen meter offer a great value in a portable
and compact design. Bring the Starter TDS Meter wherever your need to measure the combined content of all
organic and inorganic substances in a liquid takes you.
  • TDS Meters: ST20T-B, ST20T-A, ST10T-B, ST10T-A
Multi Parameter Meter Specifications
Model ST20M-B ST20M-C
Measurement Range pH 0 - 14
Conductivity 0 … 1999 μS/cm 0 … 19.99 mS/cm
TDS 0 … 1000 mg/L N/A
Salinity N/A 0.0–10.0 ppt
Temperature 0 - 99.0 °C

pH 0.01 pH
Conductivity 1μS/cm 0.01 mS/cm
TDS 1 mg/L NA
Salinity NA 0.1 ppt
Temperature 0.1 °C

pH ± 0.05 pH
Conductivity ± 2 % Full Scale
TDS ± 2 % Full Scale  N/A
Salinity N/A ± 2 % Full Scale
Temperature ± 0.5 °C
ATC Yes, with temperature display
ATC Range 0 - 45 °C
Calibration pH 3 point
Conductivity 1 point
Salinity N/A
IP Grade IP67
Dimensions 185 × 45 × 38 mm
Weight 110 g
Batteries 4 × 1.5V
Battery Life 100 hours
Warranty 1 year
Catalog Number Model Description Range Resolution
pH Meters
30073971 ST20 pH Pen Meter 0.00 – 14.00 pH 0.01 pH Resolution
30073970 ST10 pH Pen Meter
0.00 – 14.00 pH 0.1 pH pH Resolution
ORP Meters
30073985 ST20R ORP Pen Meter 1000mV – 1000mV  1mV
30073984 ST10R ORP Pen Meter
1000mV – 1000mV 1mV
Conductivity Meters
30073977 ST20C-C Conductivity Pen Meter 0.00 – 19.99 mS/cm 10 μS/cm
30073976 ST20C-B Conductivity Pen Meter   0 – 1999 μS/cm 1 μS/cm
30073975 ST20C-A Conductivity Pen Meter 0.0 – 199.9 μS/cm 0.1 μS/cm
30073974 ST10C-C Conductivity Pen Meter 0.00 – 19.99 mS/cm 10 μS/cm
30073973 ST10C-B Conductivity Pen Meter 0 – 1999 μS/cm 1 μS/cm
30073972 ST10C-A Conductivity Pen Meter 0.0 – 199.9 μS/cm 0.1 μS/cm
Salinity Meters
30073983 ST20S Salinity  Pen Meter  0.0 – 80.0 ppt  0.1 ppt
30073982 ST10S Salinity  Pen Meter  0.0 – 10.0 ppt 0.1 ppt
Multi Parameter Meters
30393199 * ST20M-B Multi Parameter Pen Meter 0 - 14 pH 0.01 pH
30393200 ST20M-C Multi Parameter Pen Meter
0 - 14 pH 0.01 pH
DO Meter
30073986 ST20D DO Pen Meter 0.0 – 19.9 mg/L 0.1 mg/L
TDS Meters
30073981 ST20T-B TDS Pen Meter 0–1000 mg/L 1 mg/L
30073980 ST20T-A TDS Pen Meter 0.0–100.0 mg/L 0.1 mg/L
30073979 ST10T-B TDS Pen Meter 0–1000 mg/L 1 mg/L
30073978 ST10T-A TDS Pen Meter 0.0–100.0 mg/L 0.1 mg/L
Additional Information

Product Reviews

(0 Ratings, 0 Reviews)