Prospex Speedtimer Mechanical Chronograph

Automatic with manual winding capability

Celebrates Seiko's first precision chronographs, developed for international sporting competitions in 1964, as well as its 1969 introduction of the world's first automatic chronograph

Case diameter: 42.5mm 

Vibrant blue dial with LumiBrite hands and markers

Screwdown see-through caseback

Tri-fold push button release clasp

Chronograph measurement of up to 30 minutes of elapsed time in 1/8-second increments

Proprietary 8R46 movement includes a column wheel and vertical clutch mechanism allowing for smooth, stutter-free movement of the chronograph hand while providing longer wear and efficiency, and maintaining the power reserve better during chronograph operation