Tire pressure valve caps help save gas and make driving safer. Color-coded caps attach easily to your tire valves so you can see at a glance when your tires need air. A smart way to reduce fuel consumption, add to tire life, and improve traction for accident prevention. Screw on easily to cars, SUVs and vans. Order 32 psi for cars, 36 psi for vans/SUVs. 4 to a set.