New Era Authentic OnField Home Baseball Cap All New Era onfield caps are infused with moisture management technology, a revolutionary advancement in cap engineering that results in superior dryness, ultimate comfort and total durability. Moisture management takes away moisture away from the skin and moves it into the fabric, resulting in a cap that is cool and dry. Performance undervisor is black to reduce glare. Developed in conjunction with the MLB players themselves. 100 polyester. Made in the USA. Fitted Sizes: 6 5/8 8. Available in all MLB Teams.