I ordered two sets of the Air Alert air valve covers, and immediately installed them on my wife's car and my grandson's car. They both welcomed them because they are so easy to see and read. One of the valve covers leaked and I had to remove it. I sent an IM to the company and they immediately sent me a new set. I have had no problem with the others. My wife and Grandson enjoy being able to see the alerts and know that their tires are safe. Thank you MobStub...