--- product_id: 55298629 title: "Com-300 Ph/Tds/EC/Temp Meter" brand: "hm digital" price: "HK$1470" currency: HKD in_stock: true reviews_count: 9 category: "Hm Digital" url: https://www.desertcart.hk/products/55298629-com-300-ph-tds-ec-temp-meter store_origin: HK region: Hong Kong --- # 4-in-1 precision sensing long-lasting AAA power Β±0.5Β°C temperature accuracy Com-300 Ph/Tds/EC/Temp Meter **Brand:** hm digital **Price:** HK$1470 **Availability:** βœ… In Stock ## Summary > πŸ’§ Stay ahead of the curve with precision water insights! ## Quick Answers - **What is this?** Com-300 Ph/Tds/EC/Temp Meter by hm digital - **How much does it cost?** HK$1470 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.hk](https://www.desertcart.hk/products/55298629-com-300-ph-tds-ec-temp-meter) ## Best For - hm digital enthusiasts ## Why This Product - Trusted hm digital brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - β€’ **Smart Calibration:** Digital calibration ensures pinpoint accuracy with effortless adjustments. - β€’ **Waterproof Durability:** Rugged, waterproof design built to thrive in hydroponics, ponds, and water gardens. - β€’ **Quad-Parameter Mastery:** Simultaneously measures pH, EC, TDS, and temperature for comprehensive water analysis. - β€’ **Temperature Compensation:** Automatic Temperature Compensation (ATC) guarantees reliable data regardless of environmental changes. - β€’ **Adaptive Conductivity Modes:** Switch between 0.5 (NaCl) and 0.7 (442TM) conversion factors plus S, mS, and ppm scales for tailored readings. ## Overview The HM Digital COM-300 is a professional-grade, waterproof combo meter delivering precise measurements of pH, Electrical Conductivity, Total Dissolved Solids, and temperature. Featuring digital calibration, selectable conductivity modes, and automatic temperature compensation, it’s engineered for demanding environments like hydroponics and water gardens, empowering you with reliable, real-time water quality data. ## 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. Review: 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. Review: 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 desertcart store. ## 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 ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B075LRLVL2 | | Battery Description | 3 *1.5 V( AG-13 button cell) | | Best Sellers Rank | #337,260 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #87 in Conductivity Meters & Accessories | | Brand | HM Digital | | Brand Name | HM Digital | | Customer Reviews | 4.0 out of 5 stars 39 Reviews | | Global Trade Identification Number | 00891144000595 | | Included Components | Product^instructions | | Item Type Name | pH/TDS/EC/Temp meter | | Manufacturer | HM Digital | | Model | 716141 | | Mounting Type | Tabletop | | Part Number | 716141 | | Smart Home Compatibility | Not Smart Home Compatible | | Temperature Reading Accuracy | plus_minus_0_point_5_degrees_celsius | | UPC | 891144000595 | | Unit Count | 1.0 Count | | Upper Temperature Range | 130 Degrees Fahrenheit | | Upper Temperature Rating | 130 Degrees Fahrenheit | | Voltage | 1.5 Volts | ## Product Details - **Battery Description:** 3 *1.5 V( AG-13 button cell) - **Brand:** HM Digital - **Mounting Type:** Tabletop - **Upper Temperature Rating:** 130 Degrees Fahrenheit - **Voltage:** 1.5 Volts ## Images ![Com-300 Ph/Tds/EC/Temp Meter - Image 1](https://m.media-amazon.com/images/I/312vJe0t+vL.jpg) ## Questions & Answers **Q: What is the tds resolution of this meter? i need one that reads to the nearest whole number (i.e. 6, 23, 34).** A: That’s how it reads. It has a resolution of 1. **Q: Is the tds displayed in ppm ?** A: Yes both 0.5 & 0.7 Scales **Q: How accurate is this meter in general?** A: We have found it to be quite accurate for our needs and use it frequently. **Q: do you have tocalibrate this with powder?** A: No calibration solution ## Customer Reviews ### ⭐⭐⭐⭐⭐ Great entry level PH Meter. *by K***S on September 20, 2025* Loving it so far. It holds calibration, and after comparing it to the reading of a $3000 meter, it is extremely accurate. ### ⭐⭐⭐⭐ Super nice Meter w/critique *by X***N on May 15, 2019* 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. ### ⭐⭐⭐ Good Meter with multiple modes *by B***D on March 15, 2021* 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. ## Frequently Bought Together - HM Digital Com-300 Ph/Tds/EC/Temp Meter - HM Digital C342 TDS and EC Calibration Solution, 342 ppm (NaCl), 90 ml Volume, Transparent/Blue - HM Digital PH-STOR pH Electrode Storage Solution for Use with PH-200 or PH-80, 60cc Volume --- ## Why Shop on Desertcart? - πŸ›’ **Trusted by 1.3+ Million Shoppers** β€” Serving international shoppers since 2016 - 🌍 **Shop Globally** β€” Access 737+ million products across 21 categories - πŸ’° **No Hidden Fees** β€” All customs, duties, and taxes included in the price - πŸ”„ **15-Day Free Returns** β€” Hassle-free returns (30 days for PRO members) - πŸ”’ **Secure Payments** β€” Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** β€” Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.hk/products/55298629-com-300-ph-tds-ec-temp-meter](https://www.desertcart.hk/products/55298629-com-300-ph-tds-ec-temp-meter) --- *Product available on Desertcart Hong Kong* *Store origin: HK* *Last updated: 2026-05-27*