Saw this but have not tried it yet FWIW, Sick of the government running my life, been driving for 57 years and I can LOOK at a tire and tell if its low and if I need to get my tire gauge out and check the PSI, .Or you could just stick them in a pressurized tube like I did. Strangely I get codes when I go up to 9000 feet...………..more pressure needed for that I guess.