Blue Stripe Hat - Bamboo and Organic Cotton. With a versatile roll-up design that fits up to six months, Baby MORI bamboo and organic cotton hats are a favourite among MORI mothers. Flexible roll-up length. Bamboo organic cotton mix fine fabric. These simple and luxurious baby basics are available in classic tones. Created with the uncomplicated aesthetic of tasteful Scandinavian and Japanese designs in mind, and made with the silken touch of bamboo and cotton mixed fabrics sourced from trusted manufacturers, your baby's sensitive skin deserves no less.