Buren Micro Rotor Grand Prix Super Slender Automatic – Ref. 774501 – c. 1960s Elegant vintage Buren Grand Prix Super Slender Automatic, featuring a clean silver dial with applied hour markers and classic mid-century styling. The main highlight is the celebrated Buren calibre 1322 micro-rotor movement, one of the earliest and most historically important ultra-thin automatic calibres. Brand: Buren Model: Grand Prix Super Slender Reference: 774501 Movement: Automatic, cal. 1322 micro-rotor Case size: approx. 34 mm Case material: Stainless steel Dial: Original silver dial Crystal: Acrylic Condition: Good vintage condition, visible age-related wear and light dial patina Year: approx. 1960–1965 A highly collectible vintage Buren powered by the famous micro-rotor automatic movement, a groundbreaking innovation that allowed the watch to remain exceptionally slim while preserving automatic winding. Buren was among the pioneers of micro-rotor technology, making this piece historically significant. Good luck!