Beau Brummel is a brand mostly associated with ties from the mid 30s onwards. But they also made other things, including caps. This cap and muffler set, made of Zephyr Wool in a very bold houndstooth, probably dates to the middle-late 1950. The Sportsman model from Beau Brummell. It features a leather sweatband but with an elasticated back to fit many different sizes. Unstretched it probably fits like a US 6 7/8, fully stretched probably something like a US 7 1/4-7 3/8.