These devices typically have a maximum pressure of around 150 PSI and can inflate a car tire in a few minutes.
Many models feature a digital display to show the current tire pressure and can automatically stop inflating once a preset pressure is reached.
They can be powered by a car's 12V DC outlet (cigarette lighter) or a rechargeable battery.
Some portable air compressors also include an LED light for use in low-light conditions or roadside emergencies.