A cap hook is a decorative hat ornament fashionable from the late Middle Ages through the Tudor period, used to pin up or decorate men's hat brims. Cap hooks were made of gold, silver, or silver-gilt base metal, and might be decorated with jewels or enamelling.[1][2]
Cap hooks could be purely decorative or could carry religious or symbolic meaning. The latter form are called enseignes and may be an evolution of the medieval pilgrim badge.[1][2][3]