Zenith stole the headlines in 1969 with the world’s first high-frequency automatic chronograph movement, aptly named ‘El Primero’. With less fanfare, Zenith also launched its heavy-duty Defy watch with an angular octagonal case, groovy orange bakelite bezel, and impressive water-resistance. Nicknamed the ‘vault’, the Defy Plongeur ref. 3648 was a monster of the abyss capable […]