Chronographs often feel like pure sports gear, but the Hamilton Jazzmaster Performer Auto Chrono H36616640 proves a stopwatch can be refined. Its sunburst blue dial, matching blue leather strap and polished 42mm case bring dress-watch polish to a fully mechanical timing instrument.

Power comes from the Hamilton H-31, a Swiss automatic chronograph caliber derived from the Valjoux 7753 and upgraded to a 60-hour power reserve. It drives three subdials for running seconds and the elapsed minutes and hours, plus a date, while the tachymeter bezel lets you calculate speed over a measured distance. Through the open caseback you can watch the rotor and chronograph works in action.

Despite the complication, the case keeps its Jazzmaster manners at 15.22mm thick, and the screw-down crown and 100 meters of water resistance mean it is ready for real life. The blue tone-on-tone pairing looks equally right with grey flannel or a white oxford shirt and chinos.

Jazzmaster Performer Auto Chrono 42mm Blue (H36616640)

• Steel case, 42mm, 15.22mm height
• Sunburst blue dial with three subdials and date
• Hamilton H-31 automatic chronograph, based on Valjoux 7753
• 60-hour power reserve
• Fixed tachymeter bezel
• Sapphire crystal; open caseback
• 100 m water resistance, screw-down crown
• Blue leather strap, 22mm lug width

A mechanical chronograph with enough elegance to wear to dinner and enough capability to time the drive there.