This hat is made from Corriedale and Shetland wool except for the blue trim and ties, which are a blend of silk and bamboo.  The pale pink is fine spun two ply Shetland wool, the bright pink is Corriedale, and the lavender/pink/red/blue is a blend of several wools.  It will fit anywhere from a large 6 month old to a medium size 5 year old.  It might be a bit big for the 6 month old, thereby leaving room to grow.