Product Description
Professional 5-in-1 Waterproof pH/EC/TDS/Salinity/Temperature MeterThe HM Digital COM-300L is a professional-grade waterproof combo meter that measures pH, Electrical Conductivity (EC), Total Dissolved Solids (TDS), Salinity, and Temperature in a single rugged instrument. With IP-67 waterproof rating, digital calibration, and replaceable probe technology, this meter delivers lab-quality results for hydroponics, water treatment, aquaculture, pools, labs, and environmental testing.Key Features:
5-in-1 Measurement: Simultaneously measures pH, EC, TDS, Salinity, and Temperature with real-time display
IP-67 Waterproof: Fully submersible and floats—perfect for field testing and harsh environments
Professional Accuracy: ±2% accuracy across all parameters with factory calibration
Automatic Temperature Compensation (ATC): Three temperature coefficients ensure accurate readings across varying conditions
Digital Push-Button Calibration: Easy calibration to any point within the meter's range
Replaceable Probe: SP-C3 sensor module extends meter lifespan and reduces long-term costs
Multiple TDS Scales: 0.5 (NaCl) and 0.7 (442™) conversion factors for different applications
Large LCD Display: Easy-to-read screen shows measurement and temperature simultaneously
Auto-Off & Data Hold: Conserves battery life and freezes readings for recording
Complete Kit: Includes pH 4 & 7 buffers, storage solution, batteries, cap, and lanyard
Technical Specifications:
pH Range: 0–14 pH
EC Range: 0–9,990 µS; 0–9.99 mS
TDS Range: 0–8,560 ppm (0.7 scale); 0–5,000 ppm (0.5 scale)
Temperature Range: 0–55°C (32–130°F)
Resolution: 0.1 µS/ppm (0-99); 1 µS/ppm (100-999); 10 µS/ppm (1000-9990); 0.1°C/F
Accuracy: ±2% full scale
Probe Type: Detachable platinum electrodes & pH glass sensor with reference tube
Waterproof Rating: IP-67 (submersible, floats)
Power: 2 × AAA batteries (included)
Dimensions: 18.5 × 3.4 × 3.4 cm (7.3 × 1.3 × 1.3 in)
Weight: 164g (5.8 oz)
SKU: COM-300L
Barcode: 891144000915
Made in South Korea
Applications:Ideal for hydroponics nutrient management, water purification systems, wastewater regulation, aquaculture water quality, colloidal silver production, laboratory testing, pool & spa maintenance, environmental ecology studies, boiler & cooling tower monitoring, drinking water analysis, and food & beverage quality control.What's Included:
COM-300L meter with integrated probe
Replaceable SP-C3 sensor module
pH 4.01 calibration buffer (20ml)
pH 7.01 calibration buffer (20ml)
pH storage solution (20ml)
2 × AAA alkaline batteries
Protective translucent cap
Neck lanyard
User manual
Why Choose the COM-300L?Unlike basic testers, the COM-300L combines five critical water quality parameters in one waterproof, professional-grade instrument. The replaceable probe design means you never need to replace the entire meter—just swap the SP-C3 sensor when needed. Factory calibration for pH, EC, and TDS ensures accuracy out of the box, while digital recalibration keeps your meter precise over years of use.Maintenance & Care:Rinse the probe with distilled water after each use and store with the cap filled with pH storage solution to maintain electrode hydration. Recalibrate pH monthly or when readings drift. The replaceable SP-C3 probe typically lasts 12-18 months with proper care. Replace batteries when the low-battery indicator appears.Note: 442™ is a registered trademark of Myron L Company. Regular calibration with pH 4.01 and 7.01 buffers recommended for optimal accuracy.