This nylon/spandex headband is 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 nylon to fit a newborn and stretch comfortably as they grow into childhood. Each headband is hand sewn by women in our local community. The satin is sourced in the USA, and the trims are sourced in China and the USA and are affixed and not meant to be removed. Due to the nature of small-batch production, color and sizing can vary slightly.