An outstanding and exceptionally rare Heuer Autavia military chronograph, reference 2446C, dating to circa 1970. This remarkable timepiece is associated with the Forças Armadas Portuguesas Ultramarinas and the Portuguese military presence in São Tomé and Príncipe. It features a robust stainless-steel case, a matte black dial with three contrasting chronograph registers, luminous tritium hour markers and hands, and a bidirectional rotating bezel. Powered by the legendary manually wound Valjoux 72 calibre, a 17-jewel column-wheel chronograph movement, the Autavia combines technical precision with authentic military heritage. Its distinctive military markings and engraved caseback make it an exceptional collector’s piece, embodying the rugged functionality and timeless design that established the Autavia as one of Heuer’s most iconic vintage chronographs.