Seiko

SRPA21

Name: Seiko SRPA21
Brand: Seiko
Availability: InStock

45mm Good Value

Low $256

Median $300

High $329

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The Seiko SRPA21 pairs the Turtle’s broad, rounded case with a blue dial and red-and-blue bezel—a cheerful combination with a proper diving connection through PADI. Its nominal 45mm diameter tells only half the story: short lugs and a crown tucked down at four o’clock make it surprisingly accommodating on the wrist. The case takes its cue from Seiko’s 6309 divers of the 1970s and ’80s, but the automatic 4R36 adds hand-winding and hacking for easier everyday use.

Introduced in 2016, this PADI edition belongs to the modern Turtle’s early wave, before the King Turtle brought sapphire crystals and ceramic bezels. Choose it for the simpler dial treatment and aluminum bezel insert, rather than those later upgrades. On this reference, pay particular attention to how the bezel pip, chapter-ring markings, and dial indices line up; small alignment discrepancies are a familiar talking point among Seiko enthusiasts, and some owners tolerate them more readily than others.

MovementAutomatic

Caliber4R36

Case MaterialStainless Steel

Case Size45mm

Water Resistance200m

Lug Width22mm