Each pair is made one at a time by a single operator on nine vintage sewing machines — some from the 1940s — in Sausalito, California, about as close to genuine one-at-a-time American clothing production as exists. The Japanese gray herringbone twill is 100% cotton, built to soften and fade with wear, with four roomy patch pockets, seven belt loops, a button fly with Japanese nickel buttons, and flat-felled seams.