Universal, Genève: A steel 24-hour chronograph wristwatch, model Aero Compax, the rotating bezel with 24-hour ring, the matt white dial with alternating Arabic and baton numerals, calibrated in 24 hours, subsidiary dials for running seconds, elapsed minutes and hours, sweep centre seconds operated by two buttons in the band, the case with screwed back numbered 890101/01 2'583'961