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HM Digital

HM Digital Com-300 Ph/Tds/EC/Temp Meter

  • Based on 41 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Fresh Water Systems, Inc.
Arrives Monday, Oct 26
Order within 13 hours and 18 minutes
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Features

  • The COM-300 is an advanced waterproof combo meter with superior accuracy
  • Applications include hydroponic systems, water gardens, ponds, etc
  • Sump-type screened inlet

Description

The COM-300 is an advanced waterproof combo meter with superior accuracy. The meter measures four parameters: pH, Electrical Conductivity (EC), Total Dissolved Solids (TDS) and temperature. Features include 2 different conductivity conversion factors to convert EC to TDS using the 0.5 (NaCl) or 0.7 (442TM), as well as selectable modes for measurements in the S, mS and ppm scales. The meter incorporates automatic temperature compensation (ATC) to accommodate for discrepancies in temperature that would naturally occur, and also features digital calibration for easy and precise calibration that will yield better results.

Brand: HM Digital


Included Components: Product^instructions


Display Type: Digital


Product Care Instructions: Always keep cap spnge moist with KCl (PH) storage solution


Unit Count: 1 Count


Power Source: Battery Powered


Model Name: 716141


Number of Batteries: 2 AAA batteries required. (included)


Upper Temperature Rating: 130 °F


Reusability: Reusable


Display Type: Digital


Power Source: Battery Powered


Number of Batteries: 2 AAA batteries required. (included)


Upper Temperature Range: 130 °F


Reusability: Reusable


Indoor Outdoor Usage: Outdoor


Product Care Instructions: Always keep cap spnge moist with KCl (PH) storage solution


Unit Count: 1 Count


Brand Name: HM Digital


Included Components: Product^instructions


Model Name: 716141


Model: 716141


UPC: 891144000595


Global Trade Identification Number: 95


Manufacturer: HM Digital


Item Weight: 150 g


Item Type Name: pH/TDS/EC/Temp meter


Part Number: 716141


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, Oct 26

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

  • Klarna Financing
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  • Financing through Google Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Similar Products

Top Amazon Reviews

    • Great entry level PH Meter.
Loving it so far. It holds calibration, and after comparing it to the reading of a $3000 meter, it is extremely accurate.
Reviewed in the United States on September 20, 2025 by kenneth e penderbottoms
    • Super nice Meter w/critique
This product works as advertised and excels at it's job with one exception which is if you need to replace the sensor you can only buy it directly from the manufacturer because no one else sells it and in fact HM Digital doesn't even sell the replacement sensor at their own Amazon store.
Reviewed in the United States on May 15, 2019 by Xeen
    • Good Meter with multiple modes
This would be my second COM-300. This one came in defective, it would not take the calibration. It was throwing up errors. I have requested a replacement and expect it to be fine. I have used the first one for about 2 years and it works well.
Reviewed in the United States on March 15, 2021 by Beverage Nerd
    • NO BACKLIT SCREEN
This product is perfect and deserved of a 5 star review except one small oversight. There is no reason for an instrument of this caliber to not have a backlit screen. I'm not sure how I over looked this detail. Excels at everything as advertised. Worth the money and I will be keeping it until I find a suitable backlit replacement. Dang. ... show more
Reviewed in the United States on February 19, 2019 by Sean S.
    • Junk
It has stopped working about three months after purchase. It always had problems where it would freeze and I would have to remove the batteries and reinstall them. No support response from the company.
Reviewed in the United States on June 21, 2021 by Bob
    • Pretty cool
Works good, pretty hard to figure out at first but once you get the hang of it you’re fine
Reviewed in the United States on April 19, 2021 by Anique Mansell
    • Beginners to expert
Quick response & accuracy
Reviewed in the United States on February 25, 2020 by Dave P.
    • No included Mylar storage solution
Review Image by Ryan P.
Missing Mylar pack of storage solution. The package is open. Again, I just wonder is it used. Such incompetence
Reviewed in the United States on September 29, 2025 by Ryan P.

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