--- product_id: 30178917 title: "SM-1 1-Stage Inline TDS Monitor For Single Water Line" brand: "hm digital" price: "197.95 DT" currency: TND in_stock: true reviews_count: 5 category: "Hm Digital" url: https://www.desertcart.tn/products/30178917-sm-1-1-stage-inline-tds-monitor-for-single-water store_origin: TN region: Tunisia --- # 0-9990 ppm TDS range Auto-Off power saving Advanced microprocessor accuracy SM-1 1-Stage Inline TDS Monitor For Single Water Line **Brand:** hm digital **Price:** 197.95 DT **Availability:** ✅ In Stock ## Summary > 💧 Stay ahead of water quality—because pure water is non-negotiable! ## Quick Answers - **What is this?** SM-1 1-Stage Inline TDS Monitor For Single Water Line by hm digital - **How much does it cost?** 197.95 DT with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.tn](https://www.desertcart.tn/products/30178917-sm-1-1-stage-inline-tds-monitor-for-single-water) ## 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 - • **Seamless Installation:** Quick-connect 1/4" John Guest tee fits any standard water line in minutes. - • **Smart Power Efficiency:** Auto-off feature conserves battery life, keeping your device ready when you need it. - • **Universal Compatibility:** Perfect for reverse osmosis systems, coolers, and all water filtration setups. - • **Effortless Filter Management:** Know exactly when to replace filters—no guesswork, no wasted resources. - • **Precision Water Quality Insight:** Real-time TDS monitoring ensures your water is always pure and safe. ## Overview The HM Digital SM-1 is a battery-powered, inline TDS monitor designed for single water lines. Featuring a wide measurement range of 0-9990 ppm with high accuracy via advanced microprocessor technology, it provides real-time water quality data. Its quick-connect 1/4" tee allows easy installation under sinks or filtration systems, while the auto-off function extends battery life. Factory calibrated and recalibratable, it’s ideal for reverse osmosis and other filtration systems to ensure optimal water purity and timely filter changes. ## Description HM Digital SM-1 In-Line Single TDS Monitor, 1/4" Tee, SM1 FEATURES Displays TDS level of a single water line. Highly efficient and accurate due to its advanced microprocessor technology. Auto-Off function conserves battery power. The unit shuts off automatically after 10 minutes of non-use. Wide Range 0-9990 ppm (From 0 - 999 ppm the resolution is 1 ppm. From 1000 to 9990 ppm, the resolution is 10 ppm, indicated by a blinking 'x10' image.) Factory Calibrated: our meters are calibrated with a 342 ppm NaCl solution. Meters can be recalibrated with a mini-screwdriver. Comes equipped with John Guest Quick-Connect T-fitting (1/4 inch standard). Installs quickly and easily. NEW PRODUCT! ## Features - Measure the product water at any time. - Use the monitor to determine when the filters need to be changed. - Ideal for any water filtration system, including reverse osmosis systems, coolers and much more. ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B00H1267XY | | Best Sellers Rank | #158,054 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #52 in Water Purification System Accessories #913 in Substance Analysis Instrumentation | | Brand | HM Digital | | Brand Name | HM Digital | | Container Type | Cartridge | | Customer Reviews | 4.4 out of 5 stars 30 Reviews | | Included Components | Battery | | Installation Type | Under Sink | | Manufacturer | HM Digital | | Material | Plastic | | Material Type | Plastic | | Model Name | SM-1 | | Model Number | SM-1 | | Other Special Features of the Product | Built In TDS Meter | | Package Information | Cartridge | | Part Number | 343433 | | Power Source | Battery Powered | | Purification Method | Reverse Osmosis | | Special Feature | Built In TDS Meter | ## Product Details - **Brand:** HM Digital - **Included Components:** Battery - **Installation Type:** Under Sink - **Manufacturer:** HM Digital - **Material:** Plastic - **Model Name:** SM-1 - **Package Information:** Cartridge - **Power Source:** Battery Powered - **Purification Method:** Reverse Osmosis - **Special Feature:** Built In TDS Meter ## Images ![SM-1 1-Stage Inline TDS Monitor For Single Water Line - Image 1](https://m.media-amazon.com/images/I/41soFBslGcL.jpg) ## Questions & Answers **Q: Can I just dip the probe in water or does it have to be use with tubing?** A: You can use this in either way. **Q: what's the accuracy of the measurement?** A: Hi Rick A. I expect to receive the item this upcoming Sunday, once I install it,I will give you feedback, I have purchased several items from HM, such as a inline tds and am finding good results as far as accuracy with in 10 tds from the hand held meter. **Q: can this be used on a 1" copper water main and if so, if I was to insert a 1" copper T, how close does the sensor need to be to the water flow?** A: Hi, if you are talking about the HM gallons meter, it could be installed with a 1" tee if you can also add a 1/4 fitting either push in type, or a threaded reduced fitting to recieve a push in pvc 1/4 npt. You can also forget the tee and use a pierce fitting on the line that is commonly used to get water to a evaporated cooler. The line should go to the in only feeding the Ro system so your not measuring all of the water being used for everything else. I hope this helps and makes sense. **Q: What is the size of the display?** A: It's small... approx. 10mm x 20mm, but it's very easy to read. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Review *by S***S on March 23, 2025* ### ⭐⭐⭐⭐⭐ Review *by J***. on December 16, 2020* ### ⭐⭐⭐⭐ Review *by S***N on March 23, 2025* ## Frequently Bought Together - HM Digital SM-1 1-Stage Inline TDS Monitor For Single Water Line - AquaticLife Float Valve Kit for RO & RO/DI Systems - HM Digital DM-1 In-Line Dual TDS Monitor, 0-9990 ppm Range, +/- 2% Readout Accuracy,Blue & White --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.tn/products/30178917-sm-1-1-stage-inline-tds-monitor-for-single-water](https://www.desertcart.tn/products/30178917-sm-1-1-stage-inline-tds-monitor-for-single-water) --- *Product available on Desertcart Tunisia* *Store origin: TN* *Last updated: 2026-08-01*