【Usage Period】 ・Size S: Approximately 2 months The usage period coincided with the time when my child was shedding a lot of hair. Due to the material, hair tends to get trapped, so some hair remains on the pillow. I will remove as much as possible before sending it, but please refrain from purchasing if you are concerned. 【Official】 Pillow to Prevent Flat Head Syndrome, Usable from Newborns Size: S (approx. 200 x 300 x 40mm) Suitable Size: Head circumference under 41cm Estimated Age: Approximately 0-6 months Box not included.