Abstract: The disclosure relates to headwear, the headwear including a hat body and a size adjustment mechanism positioned along a flap in an interior of the hat body, where the size adjustment mechanism includes a cord extending along a first side of the flap and having a first end fixedly attached to the interior of the hat body and a second end removably attachable to a second side of the flap via a fastener. The headwear is lightweight, devoid of any rigid or bulky components and is configured to bend or flex at any portion of the headwear without permanently deforming the headwear.