If your car is not equipped with a fancy Tire Pressure Monitoring System (TPMS), then you have to do manual checks now and then. Having the right air pressure in your tires is essential for safety and mileage, but checking manually is a pain in the posterior, especially if it’s really cold outside. The RightPSI tire caps change colour depending on whether you’re right on target, or have fallen off. A simple glance at your wheel can tell you if it needs attention. Heck, even if you have TPMS, RightPSI can be useful since it’ll tell you which of your tires is going flat, without you having to test them one by one. The way it works is you purchase a PSI specific set, which you cannot change if ever you change cars or tires. At $25 for a set of 4 though, you won’t be breaking the bank.
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Seems smart. I ordered the 6 unit set, one for my car, and one for my motorcycle.