This is the stylish and high-performance Hamilton Jazzmaster Performer Auto Chrono, identified by the reference number H36616640. This model perfectly blends sporty functionality with the elegant aesthetic of the Jazzmaster collection. It is powered by a reliable Swiss-made automatic chronograph movement and features a design inspired by motor racing. Brand: Hamilton Model Name: Jazzmaster Performer Automatic Chronograph Reference Number: H36616640 Gender: Men's Movement: Automatic Mechanical Chronograph (Self-Winding) Caliber: Hamilton Caliber H-31 Power Reserve: Approximately 60 hours Case Material: Stainless Steel Case Diameter: 42mm (excluding crown) Case Thickness: Approx. 15.22mm Dial Color: Blue Crystal: Scratch Resistant Sapphire Crystal with Anti-reflection treatment Case Back: Exhibition Case Back (See-through) Crown: Screw-down crown Functions: Chronograph, Date Display, Tachymeter (measures speed) Water Resistance: 10 bar (100m / 330 feet) (Note: As a pre-owned watch, professional pressure testing is recommended to guarantee water resistance.)