Made from high quality metal and rubber, durable and long lasting, Little handy unit, great for outdoor sports, camping and much more. Easy-to-read pressure gauge and easy to use, 10 ft. cord with cigarette lighter plug, great mobility for road-side assistance, It is must-have on the highway, field, or morning and evening commute when the tire flat or suddenly plunge nails, in case of any emergence, Strictly use it within instructed power voltage DC 12V, do not use high voltage, The car motor should be started before using, It’s better to stop a while after inflating for 15 minutes to extend the lifespan of the motor, Generally, when inflate approximately 3 minutes the normal tire pressure can reach 220KPA Large tires will need longer time If the gauge pointer rapidly rising when start inflate means there is no air going though the tire, you must stop and star over, otherwise, the gauge and the motor will be damaged