Kavita Corporation

The COM-80 meter is easily the most advanced series, economically priced, and reliable combo EC/TDS meter. With its versatility and durability, it is ideal for testing applications such as hydroponics & gardening, pools & spas, aquariums & reef tanks, water ionizers, drinking water, and more. It has a built-in sensor for Automatic Temperature Compensation (ATC), which ensures readings are always accurate at various temperatures.

The COM-80 Meter from HM Digital is a small, easy-to-use device that checks water quality by measuring EC (Electrical Conductivity) and TDS (Total Dissolved Solids).

It is helpful in many areas where water quality is important. 

1.    Water Treatment and Purification
2.    Hydroponics and Aquaculture
3.    Environmental Monitoring
4.    Pool and Spa Maintenance
5.    Beverage and Food Production
6.    Agriculture and Irrigation
7.    Aquariums and Fish Tanks
8.    Industrial and Cooling Systems

HM Digital TDS-EZ Meter accurately measures total dissolved solids (0–9990 ppm) to ensure water purity for drinking, aquariums, and filtration systems. With ±3% accuracy, digital display and long battery life, it’s portable, durable and easy to use—ideal for reliable water quality testing at home or work.

Range: 0 – 9990 ppm (mg/L)

Resolution: 0-999: 1 ppm; 1000-9990: 10 ppm (indicated by a ‘x10’ icon)

Accuracy: +/- 3%

EC-to-TDS Conversion Factor: NaCl (avg. 0.5)

Power source: 2 x 1.5V button cell batteries (included) (LR44 or equivalent)

Battery life: Approx. 1000 hours of usage

Dimensions: 15.5 x 3.1 x 2.3cm (6.1 x 1.25 x 1 inches)

Meter weight: 56.7g (2 oz)

Weight with package: 76.5g (2.7 oz)

• Measures Potential Hydrogen (pH), Electrical Conductivity (EC), Total Dissolved Solids (TDS), Salinity and Temperature
• Five scales: pH, µS, mS, ppm 0.5 (NaCl) Scale & 0.7 (442™) Scale
• Automatic Temperature Compensation (ATC) using three temperature coefficients
• Digital Calibration (push button) to any point within the meter’s range
• Auto-off function, data-hold function and low-battery indicator
• Large and easy-to-read LCD Screen
• Displays 3 parameters (pH/EC or TDS/Temp) simultaneously.
• Replaceable Sensors (model SP-C2 for Conductivity, SP-P5 for pH)
• Factory Calibrated (pH/EC/TDS)
• Includes protective rubber boot, 2 (AA) alkaline batteries, pH 4 & 7 calibration solutions, pH storage solution

• Range: 0 – 999 ppm (mg/L)
• Resolution: 1 ppm (0-999 ppm)
• Accuracy: +/- 3%
• EC-to-TDS Conversion Factor: NaCl (avg. 0.5)
• Power source: 2 x 1.5V button cell batteries (included) (357A or equivalent)
• Battery life: Approx. 1000 hours of usage
• Dimensions: 14 x 2.3 x 1.5 cm (5.5 x 0.9 x 0.75 inches)
• Meter weight: 31.2g (1.1 oz)

HM Digital COM-300L is a professional-grade multifunction meter that measures pH, EC, TDS, salinity, and temperature with high precision. Ideal for hydroponics, aquaculture, labs, and water purification, it features five scales (pH, µS, mS, ppm 0.5 & 0.7), automatic temperature compensation, and digital calibration. Its waterproof IP-67 housing, large LCD display, and replaceable SP-C3 sensor ensure durability and ease of use. Includes pH 4 & 7 buffer solutions, storage solution, batteries, and lanyard.

pH Range: 0 – 14 pH

EC Range: 0 – 9990 µS; 0 – 9.99 mS

TDS Range: 0 – 8560 ppm (0.7 Scale); 0 – 5000 ppm (0.5 Scale)

Temperature Range: 0-55 °C; 32-130°F

Resolution: 0-99: 0.1 µS/ppm/ 0.01mS ; 100-999: 1 µS/ppm; 1000-9990: 10 µS/ppm. Temp. resolution is 0.1 °C/F

Accuracy: +/- 2%

EC to TDS Conversion Factor: Non-linear conversions for KCl, 442TM, or NaCl solutions, selected by the user

Probe: Detachable platinum electrodes & pH glass sensor with reference tube electrodes

Housing: IP-67 Waterproof (submersible; floats)

Power source: 2 x Triple A (AAA) included

Dimensions: 18.5 x 3.4 x 3.4 cm (7.3 x 1.3 x 1.3 inches)

Weight: 164g (5.8 oz)

442 is a registered trademark of the Myron L Company

• EC Range: 0-9999 µS (µS/cm)
• Temperature Range: 0-80 °C; 32-176 °F
• Resolution: 1 µS; Temp. resolution is 0.1 °C/F
• Accuracy: +/- 2%
• Calibration: Digital calibration by push button.
• Housing: Water-resistant
• Power source: 1 x 3V button cell (included) (model CR2032)
• Dimensions: 15 x 2.8 x 1.3 cm (5.9 x 1.1 x .5 inches)
• Weight: 42.5 g (1.5 oz)
• UPC: 891144000137
• U.S. PATENT D602,384S

HM Digital HM-100 Multi-Parameter Water Quality Monitor measures pH, EC, TDS, salinity, and temperature with high accuracy. It features automatic temperature compensation, digital calibration, and a large LCD displaying multiple parameters simultaneously. Equipped with replaceable sensors and factory calibration, it’s ideal for hydroponics, RO systems, aquariums, labs, pools, and water treatment. Includes power cable, pH 4 & 7 buffer solutions, and storage solution for precise testing.

• Measures Potential Hydrogen (pH), Electrical Conductivity (EC), Total Dissolved Solids (TDS), Salinity and Temperature
• Four scales: pH, mS, ppm 0.5 (NaCl) Scale & 0.7 (442™) Scale
• Automatic Temperature Compensation (ATC) using three temperature coefficients
• Digital Calibration (push button) to any point within the meter’s range
• Data-hold function (Max. 6 data values)
• Large and easy-to-read LCD Screen
• Displays 3 parameters (pH/EC or TDS/Temp) simultaneously.
• Replaceable Sensors (model SP-C2 for Conductivity, SP-P5 for pH)
• Factory Calibrated (pH/EC/TDS)
• Includes power cable, pH 4 & 7 calibration solutions, pH storage solution