The baseline body temperature of a newborn is 37.5°C, which is higher than that of an adult. Therefore, it is important to create an environment that allows for proper heat dissipation and maintains their body temperature. If heat dissipation is not efficient, the baby may develop a rash all over the body. It’s crucial to create an environment where sweat doesn’t build up from the start. For a cool, open feel, only the necessary arm sleeves were left, and the lower body was kept cool by removing the pants. This design is optimized for ventilation and heat management. The cool hole in the middle of the chest is the wind hole. This wind hole helps the baby’s sweat and heat to be expelled. Instead of trapping heat inside the clothes, the wind hole allows for unrestricted heat dissipation, helping to maintain a comfortable skin condition. The design without pants increases breathability and convenience, allowing for easy diaper changes without the hassle of fastening and unfastening buttons every time. The wind hole in the center of the chest prevents the zipper from rolling up and touching the face.