KAIWEETS KVBF01 Brake Fluid Tester Pen

The KAIWEETS Brake Fluid Tester Pen is a handy and reliable tool for checking brake fluid moisture levels. As someone who regularly maintains vehicles, this device has proven to be a great addition to my toolkit. Here's my detailed review:Accuracy & PerformanceThe tester is highly precise, providing quick and accurate readings of moisture levels in brake fluid. It's compatible with DOT3, DOT4, and DOT5.1 fluids, which makes it versatile for most vehicles. The LED indicators are bright and easy to read, so there's no confusion about the results.Build QualityThe corrosion-resistant probe is a standout feature. It's durable and designed to withstand frequent use without deteriorating. The overall construction of the pen feels sturdy and well-made.Ease of UseThe tester is simple to operate: just dip the probe into the brake fluid, press the button, and read the results. However, checking brake fluid in reservoirs with mesh guards or long necks can be challenging. The probe isn't long or narrow enough to navigate through these obstructions easily, which may require extra effort or workarounds.PortabilityThe compact, pen-like design makes it easy to carry around, and it fits neatly in a toolbox or even a pocket. This portability is excellent for quick diagnostics on multiple vehicles.Room for ImprovementTo improve usability, the probe could be redesigned to better access brake fluid reservoirs with mesh guards or awkward angles. A slightly longer or more flexible probe would make this tester even more practical.OverallThe KAIWEETS Brake Fluid Tester Pen is a reliable and precise tool for monitoring brake fluid moisture levels, helping to ensure vehicle safety. While it struggles with certain reservoir designs, it's still a valuable addition to any mechanic's or DIYer's arsenal. A decent value for the money.

I like that it gives an exact percentage (for example: 2.5%) for the fluid so that you know exactly what's going on.

When cars are taken in for some service, it seems like the service writer wants to add to the maintenance by stating that the brake fluid needs to be changed. I would question this. So now, I have an instrument that will show if it does. Mine did not. Same for a friend too.

I used this tester multiple times over a few months on a couple bottles of "Old" brake fluid. I also checked the brake fluid in 2 of my vehicles that I had recently (within the past 6 months) flushed the fluid.I based my results on the "DOT 4" setting (DOT 3 read a few tenths higher moisture content).My smaller, older, 12 ounce bottle read between 1.6 and 2.2 but mostly in the 1.6-1.8 range. Still 'good'/green (when <2.0%).My 32 oz bottle of old fluid read between 1.4 and 1.8.On my 1998 Ranger that was partially flushed 6 months ago, I got readings between 1.6 and 1.8 but it held steady at 1.6 (higher than I expected).My 2011 Mustang, fully flushed 6 months ago, was fairly consistent at 1.4 (also higher than I expected).I did not test a new bottle because I did not want to open a sealed container then have it sit around waiting to be used.In reading other reviews I agree that the tool may be useful as a guide, but it's not a definite answer without considering other factors, like the color of the brake fluid and how long since the last brake flush.And, yes, the display is upside-down when using the tool.Review of: $16 KAIWEETS Brake Fluid Tester Pen with Corrosion Resistance Probe, High-Precision Brake Fluid Moisture Tester with Data Hold Function, Buzzer Alarm, 3 Colors Backlight, Calibrated for DOT3, DOT4, DOT5.1

Nice unit, excellent quality and function. Outstanding price. This is part of my regular diagnostics, along with the oil change. Simple enough that you can have someone who's not a 'shade-tree mechanic' do the check for you. Beats the daylights out of the low-quality 'good/bad indicator' ones out there.