How to use 1. For accuracy, check pressure when tires are cold. Pressure increase with heat. Tires can lose one pound per month under normal conditions. Proper tire pressure improves gas, mileage, handling, braking and durability. 2. To avoid the possibility of eye injury, eye protection must be worn when using the gauge. 3. Do not exceed maximum pressure on gauge. 4. Dropping or severe jarring may impair accuracy of What's in the box 1 x Inflating gun