Multiple Function Pressure Indicating Valve Cap (27-31psi) (32-36psi) Easily check tire pressure with one quick look. Valve cap does not need to be removed to check tire pressure with a gauge or to inflate tire Valve caps indicates either a safe pressure condition or a low pressure warning. Avoid the grit and road grime usually left on your hands during tire pressure checks. Proper tire inflation helps improve gas mileage and reduces tire wear.