--- product_id: 481730839 title: "Brake Fluid Liquid Tester,Hydraulic Fluid Liquid Oil Moisture Analyzer with 5 Led Indicators,DOT 3 DOT 4 DOT 5.1 Brake Fluid Liquid Tester Pen for Check Engine Car Accessories" brand: "patonu" price: "AR$22821" currency: ARS in_stock: true reviews_count: 10 category: "Patonu" url: https://www.desertcart.com.ar/products/481730839-brake-fluid-liquid-tester-hydraulic-fluid-liquid-oil-moisture-analyzer store_origin: AR region: Argentina --- # 1% accuracy in seconds auto power-off after 20s nickel-plated corrosion-resistant probe Brake Fluid Liquid Tester,Hydraulic Fluid Liquid Oil Moisture Analyzer with 5 Led Indicators,DOT 3 DOT 4 DOT 5.1 Brake Fluid Liquid Tester Pen for Check Engine Car Accessories **Brand:** patonu **Price:** AR$22821 **Availability:** ✅ In Stock ## Summary > 🚗 Don’t brake your safety—test it like a pro! ## Quick Answers - **What is this?** Brake Fluid Liquid Tester,Hydraulic Fluid Liquid Oil Moisture Analyzer with 5 Led Indicators,DOT 3 DOT 4 DOT 5.1 Brake Fluid Liquid Tester Pen for Check Engine Car Accessories by patonu - **How much does it cost?** AR$22821 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.com.ar](https://www.desertcart.com.ar/products/481730839-brake-fluid-liquid-tester-hydraulic-fluid-liquid-oil-moisture-analyzer) ## Best For - patonu enthusiasts ## Why This Product - Trusted patonu brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Smart Power Saving:** Automatic shutdown after 20 seconds extends battery life so your tester is ready when you are. - • **Safety First, Always:** Instantly know when to replace brake fluid to avoid accidents and keep your ride smooth and secure. - • **Universal Compatibility:** Effortlessly test DOT 3, DOT 4, and DOT 5.1 brake fluids—perfect for personal use or professional workshops. - • **Durable & Reliable Build:** Nickel-plated metal probe resists oil and oxidation, ensuring long-lasting, consistent performance. - • **Precision at Your Fingertips:** Get brake fluid moisture levels with 1% accuracy in just seconds—no guesswork, only confidence. ## Overview The Patonu Brake Fluid Liquid Tester is a compact, high-precision tool designed to measure moisture content in DOT 3, DOT 4, and DOT 5.1 brake fluids with 1% accuracy. Featuring a corrosion-resistant nickel-plated probe and a skid-resistant matte black case, it delivers fast results via a 5-LED indicator system. Its automatic 20-second power-off function conserves battery life, making it ideal for both personal vehicle owners and professional mechanics aiming to maintain optimal brake performance and safety. ## Description The probe of the brake fluid detector is made of high quality metal to prevent oil and oxidation; The shell is matte black plastic for better skid resistance and excellent overall feel.This product can quickly check the health condition of your car brake fluid, remind you to replace the brake fluid when necessary, so as to avoid traffic accidents, so that you are more comfortable and safer.Suitable for testing DOT3, DOT4, DOT5.1 brake oil performance. The polarization phenomenon in brake fluid test process is greatly reduced by AC pulse test method. The test result is accurate and the measurement speed is fast.The LED indicator will show the percentage of water in the brake fluid in three colors: green, yellow and red. Red indicates brake fluid needs to be replaced immediately, green indicates good condition, and yellow indicates acceptable condition but soon replaced.To save power, remove the battery and clean the detector after the test. This better prevents corrosion and protects the brake fluid tester. Review: Simple to Use Device That Works - Works great. Tested on a small sample first to confirm accuracy. Clean sample tested correctly. Added a relatively small amount of water to the sample and this device instantly recognized the presence of water in the brake fluid. My device says "Battery Tester" so I'm assuming this also works to test for presence of water in car batteries, but I've only tested this with brake fluid. Handy to have and provides peace of mind against water contamination in brake fluid whether the fluid is tested in use or to test a bottle of brake fluid that has previously been opened and stored for awhile. Simple to use, didn't need to reference instructions. This isn't a tool that shouldn't experience damaging contact through normal use, and the construction is sufficient for careful use, but dropping it onto a hard surface may cause fatal damage. Should be okay in a professional environment requiring frequent use, as long as care is taken- it is a measuring instrument after all. Review: It works. Well it worked anyway - It definetly works but if you even think there's a possibility of moisture in your fluid just change it. But it definetly worked on some old fluid i already knew needed to be changed. Only issue i have with it is after testing it i dropped it from about waist high and that was that. No more fluid tester. I supppose if i were more patient i could have at least tried to put it back together but I'm not and i didn't. Not the sturdiest thing thats for sure. ## Features - High Quality Performance: The brake fluid detector uses nickel plated metal probe, oil and oxidation resistant, not easy to corrosion. The case is matte black plastic for better skid resistance and good body texture. Metrics are accurate to 1% and results are received within seconds. Help you understand the brake fluid more clearly. - Safe Driving: This product can quickly check the health condition of your car brake fluid and remind you to change the brake fluid when necessary to avoid traffic accidents, so that you are more comfortable and safer. - Easy Operation: Brake fluid detector is easy to use, and small size easy to carry. Press the button, insert the test pen, it only takes a few seconds to know the result through the LED, in order to save power, this test pen has automatic shutdown function. It will automatically turn off the power after 20 seconds each time to save power. - Wide Application Range: can be used in most cars. It is suitable for detecting the moisture content in DOT-3, DOT-4, DOT-5.1 brake fluid. It is very convenient for personal use and widely used in individual workshops, repair shops and dealer workshops. - Service Guarantee: The brake fluid detector requires 1 LR03 AAA 1.5V battery. Our package does not include batteries, please buy batteries at local market. We offer a one-year warranty. If you cannot confirm its compatibility, or have any questions, please feel free to contact us. ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B0BGHX92V1 | | Best Sellers Rank | #317,833 in Automotive ( See Top 100 in Automotive ) #95 in Brake Fluids | | Brand | Patonu | | Customer Reviews | 4.2 4.2 out of 5 stars (439) | | Date First Available | September 26, 2022 | | Item Weight | 0.634 ounces | | Manufacturer | Patonu | | Manufacturer Part Number | Patonu-TST111 | | Package Dimensions | 5.98 x 1.34 x 0.75 inches | ## Images ![Brake Fluid Liquid Tester,Hydraulic Fluid Liquid Oil Moisture Analyzer with 5 Led Indicators,DOT 3 DOT 4 DOT 5.1 Brake Fluid Liquid Tester Pen for Check Engine Car Accessories - Image 1](https://m.media-amazon.com/images/I/61v4DKCZ4EL.jpg) ![Brake Fluid Liquid Tester,Hydraulic Fluid Liquid Oil Moisture Analyzer with 5 Led Indicators,DOT 3 DOT 4 DOT 5.1 Brake Fluid Liquid Tester Pen for Check Engine Car Accessories - Image 2](https://m.media-amazon.com/images/I/71nfPeYUD7L.jpg) ![Brake Fluid Liquid Tester,Hydraulic Fluid Liquid Oil Moisture Analyzer with 5 Led Indicators,DOT 3 DOT 4 DOT 5.1 Brake Fluid Liquid Tester Pen for Check Engine Car Accessories - Image 3](https://m.media-amazon.com/images/I/71SC5ZW3JnL.jpg) ![Brake Fluid Liquid Tester,Hydraulic Fluid Liquid Oil Moisture Analyzer with 5 Led Indicators,DOT 3 DOT 4 DOT 5.1 Brake Fluid Liquid Tester Pen for Check Engine Car Accessories - Image 4](https://m.media-amazon.com/images/I/71dCGD5I6OL.jpg) ![Brake Fluid Liquid Tester,Hydraulic Fluid Liquid Oil Moisture Analyzer with 5 Led Indicators,DOT 3 DOT 4 DOT 5.1 Brake Fluid Liquid Tester Pen for Check Engine Car Accessories - Image 5](https://m.media-amazon.com/images/I/711AJdXbyXL.jpg) ## Customer Reviews ### ⭐⭐⭐⭐⭐ Simple to Use Device That Works *by H***Y on September 5, 2025* Works great. Tested on a small sample first to confirm accuracy. Clean sample tested correctly. Added a relatively small amount of water to the sample and this device instantly recognized the presence of water in the brake fluid. My device says "Battery Tester" so I'm assuming this also works to test for presence of water in car batteries, but I've only tested this with brake fluid. Handy to have and provides peace of mind against water contamination in brake fluid whether the fluid is tested in use or to test a bottle of brake fluid that has previously been opened and stored for awhile. Simple to use, didn't need to reference instructions. This isn't a tool that shouldn't experience damaging contact through normal use, and the construction is sufficient for careful use, but dropping it onto a hard surface may cause fatal damage. Should be okay in a professional environment requiring frequent use, as long as care is taken- it is a measuring instrument after all. ### ⭐⭐⭐⭐ It works. Well it worked anyway *by J***E on August 4, 2025* It definetly works but if you even think there's a possibility of moisture in your fluid just change it. But it definetly worked on some old fluid i already knew needed to be changed. Only issue i have with it is after testing it i dropped it from about waist high and that was that. No more fluid tester. I supppose if i were more patient i could have at least tried to put it back together but I'm not and i didn't. Not the sturdiest thing thats for sure. ### ⭐⭐⭐⭐⭐ Super useful! *by R***N on March 11, 2023* So I was debating doing a brake fluid flush becausey fluid is nasty looking and lots of travel in brakes. Bought this because I figured it was cheap and why not try it out. HOLY CRUD! So my brake fluid light this up like Christmas! All the lights light up indicating the fluid needs to be replaced immediately. Was still a little skeptical because my brake fluid wasn't too terribly old so I decided to check a bottle of DOT 3 brake fluid I had lying around that I opened about 3 1/2 years ago (I was thinking that the device was not working and it just said it was bad to get me to replace fluid) BUT NO! When I tested that old bottle that I kept the lid on tight for those years never opening again it came at as O.K. to use! So I went back and checked car againand it light right back up, so that confirms it in my mind that this thing WORKS! Love it! I even ran around the house testing random things to check the water content...........yes. it works. For $8......BUY IT!!!!!!!! ## Frequently Bought Together - Brake Fluid Liquid Tester,Hydraulic Fluid Liquid Oil Moisture Analyzer with 5 Led Indicators,DOT 3 DOT 4 DOT 5.1 Brake Fluid Liquid Tester Pen for Check Engine Car Accessories - Prestone AS401 DOT 3 Synthetic Brake Fluid - 32 oz. --- ## 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.com.ar/products/481730839-brake-fluid-liquid-tester-hydraulic-fluid-liquid-oil-moisture-analyzer](https://www.desertcart.com.ar/products/481730839-brake-fluid-liquid-tester-hydraulic-fluid-liquid-oil-moisture-analyzer) --- *Product available on Desertcart Argentina* *Store origin: AR* *Last updated: 2026-09-14*