Brake Fluid Liquid Tester Pen,1PC DOT 3 DOT 4 DOT 5.1 Brake Fluid Liquid Tester Pen, Car Diagnostic Testing Tool with 5 LED Indicators, Hydraulic Fluid Liquid Oil Moisture Analyzer

I hesitantly bought this Brake fluid liquid tester to see if it works or a gimmick, and to my surprise, it actually works. My initial test showed that I needed to replace my brake fluids due to water being in the line. So I bled my brakes, retested my brake fluid, and it passed, indicating no water. I am amazed and pleased that it actually works. Saves me a trip to the mechanic shop.

What this tester tests for is moisture in your brake fluid. This is a cheap tester, but it does a very good job testing for moisture. The size is very small and it can fit in your pocket like a pin the light on it or bright so you shouldn’t have a problem seeing what your test result is it fits a triple AAA battery so the battery life depends on what type of battery you put in it and I honestly would recommend anybody who works on their own cars to have one of these in our toolbox. It’s not like it will break the bank because it’s very cheap but this does work if you put it on anything with water on it, it will go red. I bought this to test my brake fluid and my brake fluid needs to be changed because it has a high moisture level and I would’ve not known, unless I had a tester like this one

This is my second one of these. They work great, easy to use and seem to be accurate. However, you have to be careful not to dip the probes too deep. The plastic will eventually start to crumble. Apparently it is not resistant to brake fluid. Just insert the probes enough to measure and then wipe them dry. My first one lasted a couple of years, but the last time I used it, it was on a vehicle that I couldn't see where the fluid level was and accidentally got it too deep. I dried it off, but some must have entered inside. The next time I used it was a few months later and when I pulled the cap off, the plastic around the tips just came apart. As cheap as they are, I just bought another one. I'll be more careful this time.

It’s supposedly working but where I tested - in the reservoir it showed no water. Brake fluid tends to be worse closer to brakes themselves. Which I didn’t test.

Tool is functional and properly detects moisture saturation in brake fluid. Though the plastic the tool is made of and what holds the electrodes in is made of a plastic that is not resistant to brake fluid and after a few checks even with wiping off the plastic will degrade and fall apart. Good for a few uses before it breaks apart

This testes was easy to use, battery is not included. Battery was easy to install, it has lighting as you test the break fluid to show if there is moisture in the fluid. My vehicle is 14 years old and have not changed the fluid and it showed good, I tested it on new break fluid and it also tested good. I tested in water and the lights went to red showing that it was water-moisture. I still changed the break fluid on my 14 year old vehicle.

After my mechanic told me my brake fluid needed to be changed, for a nominal fee (haha), I bought this tester and found that my brake fluid was okay... a small price to avoid a larger price for replacing all my brake fluid.

Pretty basic testing pen, works good for my intended use for daily driven vehicles.

Works perfectly