Review on ANKIA Car Tire Pressure Monitoring Valve Stem Caps Sensor with 3-Color Eye Alert (Pack of 8) by Rex Bareham

I first bought them just to check my car's tire pressure to see if they were ok as sometimes the tire pressure light was on. It wasn't difficult to use once I read the manual. You just have to follow the instructions and they are so easy to use. Green means normal and red means you need more air. I tested mine and it worked very well. Also, I noticed that they can be used for your bike and even motorcycle. Maybe I should check my bike too. Overall, they are easy to use and the results are easy to read. You will receive two packages with 4 monitors each. That's enough for everyday use.