1.Remove vehicl's Black Valve cap .
2.Screw the tire indicators tightly onto the valve's stem .
3. the Green indiction-the tire pressure is at normal range .
if not ,pls check your tire pressure for your safety .
28PSI[1.93BAR] 30PSI[2.07BAR] 32PSI[2.21BAR] 34PSI[2.34BAR]
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