The product is a set of 20 branded hat sizer reducer inserts designed to make fitted hats smaller. These inserts are lightweight at 0.634 ounces and are made in China. They do not require batteries and come in a pack of 20. The part number for the product is 577664_1_kB6iwi4c, and the item model number is 577664_1_ViHMX7NDu. These hat inserts provide a convenient solution for achieving a perfect fit when wearing fitted hats.