Every woman needs a few things in her car. I'm not talking about hygiene products. This list just might keep you from becoming another damsel in distress. It's more than just having it; you need to know how to use it, too. The amount of pressure needed for you car is generally written on the inside of your car door. It's also written on the sidewall of the tires. A tire Gauge is easy to use, simply insert the tire stem and read the numbers on the gauge.