It is a pillow for exclusive use of in-car nights, which uses the same material and structure as the popular mat for exclusive use of in-car nights that is comfortable to sleep in.If you open the air valve, the air will come in naturally and it will swell. You can adjust the hardness to your liking by breathing in or letting air out.To store, just roll it up while removing the air and put it in the storage case. It can be compactly stored with a diameter of 10 cm and a length of 29 cm.The front surface (black) has a smooth and cool oxford check, and the back surface (dark gray) uses warm micro suede. It is the same as the mat only for staying in the car, which can be used according to the season.