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Models available for pH/ORP, DO, pH/conductivity and conductivity/TDS
Ohaus® Starter™ Portable Meters
Easy to use—great for both lab and field
Compact, ergonomic design fits in the palm of your hand
Choose from the economical 300 series or more advanced 400 series
Starter portable water analysis meters offer convenience, reliability and durability in a compact design. Intuitive software and a well-organized display make operation simple and straightforward. Meters track the accuracy of the calibration process right on the display for peace of mind. A retractable built-in stand lets you prop meters on a flat surface.
300 Series Meters
300 Series meters are a reliable, economical option for both the lab and field. They store 30 measurements and the last calibration data, accessible with the touch of a button. IP54 protection shields meters from damage by water and dust particles. Choose from pH/ORP, DO or conductivity/TDS meters.
400 Series Meters
pH/ORP and pH/conductivity meters feature an IP67 waterproof housing—ideal for prolonged use in wet environments. A rechargeable lithium battery ensures hours of trouble-free testing in the field, while an included rubber case protects your investment. They log up to 1000 measurements and five calibration data sets for each sensor ID. A built-in USB port enables easy data transfer.
ST400D Optical DO meters are IP54 dustproof/splashproof and operate on three AAA batteries. They log 99 measurements and the last calibration for recall.
Click on stock #s for complete information and pricing.
ST300 Meter and Electrode (90335) ST300 Meter & Electrode 90335
ST400 Meter and Electrode (90310) ST400 Meter & Electrode 90310 shown with included meter protector
pH/ORP Meters
300 Series pH/ORP Meters
Reliable and economical
Easy-to-read screen
Meters & Meter Kits
MFR # DESCRIPTION STOCK #
ST300-B Meter Only 90334
ST300 Meter & ST320 Electrode 90335
ST300-G Meter, ST320 Electrode and Soft Case 90336
Replacement Items & Accessories
DESCRIPTION STOCK #
ST320 pH Electrode with ATC, Single Junction, Plastic Body 90318
pH Electrode, Double Junction, Plastic Body (Requires Temperature Probe) 86299
ORP Electrode, Double Junction, Epoxy Body 86317
Temperature Probe, Stainless Steel 90319
Rayovac® Ultra Pro Alkaline Batteries, AAA, Pack of 24 13429
400 Series pH/ORP Meters
Log up to 1000 measurement data sets
Onscreen prompts for quick, easy setup
Waterproof IP67 housing
Meters & Meter Kits
MFR # DESCRIPTION STOCK #
ST400-B Meter Only 90309
ST400-F Meter & ST320 Electrode 90310
ST400-G Meter, ST320 Electrode and Soft Case 90311
Replacement Items & Accessories
DESCRIPTION STOCK #
ST320 pH Electrode with ATC, Single Junction, Plastic Body 90318
pH Electrode, Double Junction, Plastic Body (Requires Temperature Probe) 86299
ORP Electrode, Double Junction, Epoxy Body 86317
Temperature Probe, Stainless Steel 90319
pH Buffer Pack, 500-mL Bottles (pH 4.00, 7.00, 10.00) 40328
ST300D-B Meter 90303 ST300D-B Meter 90303
ST400D Meter with Probe 90313 ST400D Meter with Probe 90313
DO Meters
300 Series DO Meters
Reliable and economical
Easy-to-read screen
Immediate measurement—galvanic DO probe requires no warm-up time
Meters & Meter Kits
MFR # DESCRIPTION STOCK #
ST300D-B Meter Only 90303
ST300D Meter, STDO21 Probe and ATC Probe 90304
ST300D-G Meter, STDO21 Probe, ATC Probe and Soft Case 90305
Replacement Items & Accessories
DESCRIPTION STOCK #
STDO21 Galvanic DO Probe 90320
ATC Probe, Stainless Steel 90319
Rayovac® Ultra Pro Alkaline Batteries, AAA, Pack of 24 13429
400 Series Portable Optical DO Meters
Accurate, low maintenance optical DO probe
Intuitive, easy-to-read display
Meters & Meter Kits
MFR # DESCRIPTION STOCK #
ST400D-B Meter Only 90312
ST400D Meter & STDO21 Probe 90313
ST400D-G Meter, STDO21 Probe and Soft Case 90314
Replacement Items & Accessories
DESCRIPTION STOCK #
STDO21 Optical DO Probe 90321
Replacement Cap for DO Probe 90322
Zero Oxygen Solution, 120 mL 29890
Rayovac® Ultra Pro Alkaline Batteries, AAA, Pack of 24 13429
ST300C-B Meter 90306 ST300C-B Meter 90306
Conductivity/TDS Meters
300 Series Conductivity/TDS Meters
Reliable and economical
Easy-to-read screen
Meters & Meter Kits
MFR # DESCRIPTION STOCK #
ST300C-B Meter Only 90306
ST300C Meter & STCON3 Probe 90307
ST300C-G Meter & STCON3 Probe with Soft Case 90308
Replacement Items & Accessories
DESCRIPTION STOCK #
STCON3 Conductivity Probe, 4-Pole 90323
Conductivity Solution, 10 µS, 500 mL 28063
Conductivity Solution, 84 µS, 500 mL 28068
Conductivity Solution, 1413 µS, 500 mL 33973
Conductivity Solution, 12.88 mS, 500 mL 74240
Rayovac® Ultra Pro Alkaline Batteries, AAA, Pack of 24 13429
ST400M-F Meter with Probes 90316 ST400M-F Meter with Probes 90316
pH/Conductivity Meters
400 Series pH/Conductivity Meters
Store, recall and download up to 1000 data sets
Onscreen prompts for quick, easy setup
Waterproof IP67 housing
Meters & Meter Kits
MFR #DESCRIPTIONSTOCK #
ST400M-BMeter Only90315
ST400M-FMeter with pH ST320 Probe & Conductivity STCON3 Probe90316
ST400M-GMeter with Probes and Case90317
Replacement Items & Accessories
DESCRIPTIONSTOCK #
pH Electrode with ATC, Sealed, Plastic Body, 3-m Cable90318
pH Electrode, Double Junction, Plastic Body (Requires Temperature Probe)86299
Conductivity Probe, 4-Pole, (70 µS to 200 mS)90323
ORP Electrode, Double Junction, Epoxy86317
Temperature Probe90319
pH Buffer Pack, 500-mL Bottles (pH 4.00, 7.00, 10.00)40328