These headbands are one size fits most and the size cannot be adjusted. The headband is sewn at a 6.5" diameter (13" circumference), keep in mind that measurement is before it stretches. We feel this is the perfect size for our soft material to fit a newborn and stretch comfortably as she grows into childhood. The bow measures approximately 4.5" across. The FAB headband is wider that our Classic styles, unrolled the width measures approximately 5". All edges of this style are raw and are intended to roll. This style is secured with adhesive once tied and is not meant to be untied. The FAB material is a soft nylon/spandex blend, produced to our specifications, in the USA . Each headband is hand sewn and tied by women in our local community. Due to the nature of small-batch production color and sizing can vary slightly.