Seiko

Tuna 300M

Name: Seiko Tuna 300M
Brand: Seiko
Availability: InStock

47.7mm

Low $850

Median $932

High $1,100

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The Seiko Tuna 300M puts its protective shroud front and center: this is a dive watch whose character comes from the hardware, not decoration. Its broad case looks formidable, but the short lugs make it surprisingly manageable on the wrist—try it before ruling it out by diameter alone.

The 7C46 quartz movement is part of the attraction, not a compromise: purpose-built for Seiko’s professional divers, it has the torque to drive those substantial, highly legible hands. For a first Tuna, an uncoated steel version gives you the clearest expression of that construction; dark-finished versions make the same architecture feel more severe.

Pay particular attention to the shroud screws and the bezel’s action, since both are working parts of the design. A battery replacement should include attention to the seals and a pressure test if you intend to take it diving.

MovementQuartz

Caliber7C46

Case MaterialStainless Steel

Case Size47.7mm

Water Resistance300m