Flat Cap Harris Tweed Navy Herringbone Harris Tweed Flat Cap Grey Herringbone With Overcheck Harris Tweed Harris Tweed Flat Cap Herringbone Cap The Cashmere Choice Harris Tweed Navy Herringbone Flat Cap Etsy Harris Tweed Flat Cap Navy Blue Herringbone Etsy. Choose this Harris Tweed flat cap in Navy Herringbone as the perfect accessory for any outfit whether it be in the city or in the field. It has a sewn down brim, quilted lining and a grosgrain sweatband for additional comfort and warmth. 100% Wool Quilted Satin Lining: 100% Polyester Grosgrain Sweatband Sewn Down Brim Removable Side Pin Woven in Scotland