The cowboy hat of the old west is the Boss of the Plains hat. The Boss of the plains hat had an open crown that was 4″ and a flat brim that was from 3 1/2 to 4″. It was generally light in color and it protected the cowboy from the hot sun in the summer and the cold in the winter. The Boss of the Plains hat is the cowboys cowboy hat. It was an important part of the cowboys outfit. In the hot summer he would have heat stroke and in the winter his ears would have been frost bitten. The cowboy felt naked without his hat.