This replica Seamaster 215304 houses a chronograph complication inside a 45.5mm Planet Ocean case, making it one of the largest and most functionally complex watches in the Seamaster family. The blue dial with three sub-registers at 3, 6, and 9 o’clock provides running seconds, 30-minute counter, and 12-hour totalizer respectively. The 215-series reference number identifies this as a Planet Ocean Chronograph with a co-axial column-wheel movement in the genuine version, placing it above time-only Planet Oceans in both size and mechanical ambition.

Build Details

• Case diameter: 45.5mm
• Case material: stainless steel
• Dial: blue with three chronograph sub-registers
• Bezel: unidirectional, ceramic with liquidmetal minute scale
• Crystal: sapphire with anti-reflective coating
• Bracelet: stainless steel with diver’s extension clasp
• Movement: automatic chronograph
• Functions: hours, minutes, small seconds, date, chronograph (30 min + 12 hr), rotating dive bezel

The column-wheel chronograph design provides a crisper pusher feel than a cam-operated alternative. The pushers themselves sit at 2 and 4 o’clock with guards that prevent accidental activation during a dive.

What Collectors Notice

Planet Ocean Chronographs attract buyers who want dive capability and timing function in one case. The 45.5mm diameter means this is not a subtle watch, but the proportions work because the chronograph sub-dials and the dive bezel fill the dial space efficiently. The blue dial version matches the ocean-themed palette that defines the Planet Ocean identity. Compared to the simpler blue 44mm 210.30.44.51.03.001 time-only version, the chronograph adds the stopwatch function but also adds 1.5mm of case diameter. Both are part of the Seamaster range, serving different levels of wrist-tool complexity.

This vs Other Versions

The Seamaster chronograph occupies a specific niche for collectors who find a standalone dive timer insufficient. The 30-minute counter handles most timed activities, while the 12-hour totalizer extends to longer intervals. The steel bracelet and diver’s extension clasp keep it anchored as a sport watch rather than a dressy chronograph. At 45.5mm it commands wrist space, but the weight distribution across the bracelet keeps it balanced during extended wear. This replica Seamaster 215304 puts the full chronograph-diver package into one case for buyers who want maximum function per square millimeter.