Features:

  • SAFE&USEFUL---The unit is Mini Pen Liquid Moisture Water Tester Tool. Check the health status of DOT3, DOT4, DOT5 car brake fluid, it will be safer for your driving.
  • 5 LED INDICATORS---5 LED to indicate percentage of water in the brake fluid with three colors green yellow and red. Even in the dark does not affect reading, make reading data easier.
  • EASY TO USE---The brake fluid tester is easy to use. Check the quality of brake fluid in car only takes seconds. Make it easier to operate for beginner. It's a must-have car tool for your car owners.
  • PORTABLE&DURABLE---Brake fluid tester pen is small compact size, easy to carry. Super strong ABS shell, has long service life.
  • AUTO TURN OFF---In order to save power, this test pen has the automatic shutdown function, it will automatically turn off the power 15 seconds after starting every time.
Wish I Had Known About This Tool Many Years Ago

Used this tool on my vehicles, and it appears to work well. At this point, all my vehicles has had fresh brake fluid installed in them previously, and with me testing, it had shown a safe reading. I will monitor my fluid as well as friends (so quick to check for an important procedure) in the future. Also, I did a comparison against brand new fluid (two days old) verses an establish fluid ( more than a year old) In both instances of testing, the "light' indicated good (less than 1 % moisture content) This gave me a base to relay upon my tester for future applications.

Already saved me money on expensive brake repairs

It just works as described. You put a AAA battery in it and push the end like a pen, which turns it on with a green led. Insert it into your brake fluid reservoir and it gives you a reading by the color coded LED lights on the side. I like this one because it works with different brake fluids dot3,4, etc. They may all do that but wanted to be sure before buying and this one had it in the description. I have used it on two vehicles so far and it works great! I found that I needed to change the fluid in one of my cars which probably saved me a lot of money already, because the fluid can retain water and start to deteriorate your brake lines and parts. This tester does seem to be a high quality piece of equipment like something an actual mechanic would use often

Great Product. Easy to Test Brake Fluid.

This product works great. I tested it on new brake fluid and on a cup of water to see if it really worked and it does. Similar products customers have complained about the plastic around the probes breaking off over time. My advice here is to always clean the test pen with denatured alcohol after use to help remove any trace of brake fluid on the surface. Doing so should really help extend the life of this tool.

Appears to work fine

Popped a AAA battery in and tested in a cup of water. It instantly shined red and indicated 4%. Next tested the brake fluid in my 2016 Nissan Rogue and it showed as 1%. Using a baster, I extracted a small amount and squirted it into a small cup. Added a few drops of water with a thin syringe and the tester still said 1%. Added another tiny amount of water and it jumped to 4%. These readings were very consistent. I'm satisfied that the tester is accurate. Not surprised that my 51,000 mile vehicle driven gently in the arid U.S. Southwest tested as only 1%. Maybe vehicles in humid environments need frequent brake fluid changes but I don't believe that's true for those in the desert. That's why I bought this tester after the local Nissan dealer tried to sell me a brake fluid change and other service. Dealers and most shops can only be trusted to try to get as much money out of us as they can con us into losing. My fluid is still very gold in color and my brakes work perfectly, so I'm opting to not change it at this time. Will test again next year. When it makes sense to do so, I'll change it myself.

avoid a nasty surprise

when your brake calipers are rusted because of water contaminated brake fluid you can even see dark or black brake fluid in the master cylinder as an early warning to problems. brake fluid is cheap and new calipers are big money so add this brake fluid test to your maintenance schedule.

Accurate way to measure moisture in brake fluid

I got a reading immediately at 1% which is very useful telling me that brake fluid is good. The device just measures voltage which correlates to water content. Simple enough.

Amazing, so cheap so valuable

How do you even know when is actually time for a brake fluid change, it depends on so many factors not only miles, you might be over doing it, it doesn't hurt anything but you are waisting time and money. Or it might be overdue and that's no bueno, with this little tool I was able to test in seconss all my 3 cars and one of them was pretty bad, indeed the fluid was very dark and had years since last change. You won't use it much maybe once every 2 years lol but for the price is nice to have.

Must have in any auto mechanics tool bag.

I purchased this because my dealership wanted $139 to change my brake fluid. After some YouTube videos and this handy tool, I was all set. Just insert 1 battery, insert tester into existing brake fluid, press button and you get an instant reading. I had no idea my brake fluid was so bad. I was also able to get factory brake fluid here on Amazon for only $8. Very handy and high quality product.

Easy to use, bright LED, fairly priced

Easy to use, competitively priced brake fluid tester. Nice bright led readouts! Highly recommended. I would, however, be very vigilant about not dropping it on a hard surface or it may suffer damage being all plastic! And be very careful with the battery door or the ears will snap off in a heartbeat.

Seems to work as expected

Seems to work. From the point i opened to when i tested my fluids, it was very straightforward to use. As for if the reading is accurate, i have no idea, BUT the reading was what i expected my fluid to be based off when i last changed my brake fluid.

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