Tortle helps to prevent and treat flat head syndrome. It does this by gently deflecting your baby"s head when she"s sitting or lying on the back of her head, to gently move her head from side to side. It"s a natural way to encourage healthy head and neck motion, without any of the suffocation risks of repositioning pillows or wedges. * Sizes: Small (0-2 months/5-10 lbs.) Medium (2-4 months/10-15 lbs.) Large (4-6 months/15-20 lbs.) * 95% cotton/5% spandex * Machine Washable * It is recommended that all newborns wear a TortleTM for the first six months of life to aid in repositioning baby"s head.