Waterproof Flat cap from Failsworth is made of 100% wool, Waterproof British tweed. 
It has a breathable Porelle coating and Teflon lining making them waterproof whilst allowing the air to circulate for warmth and comfort. 
100% Wool
Waterproof
Quilted satin/Teflon lining
Porelle coating
Sewn-down brim
Available in Shade 538 (darker one) and 570 (Greener colour)