Embody the spirit of navigation and astronomy with the Breguet Celestial Keychain, featuring a precision-crafted universal equinoctial ring dial in polished brass. Originating from the ingenious 17th-century design by John Rowley and other historical artisans, this keychain doubles as a miniature timepiece and navigational tool, reflecting a blend of art and science. It is accompanied by an instructional book, enriching your understanding of its historical and functional significance.