Vintage Watch | Seiko 6309-7040 Turtle (1981 - Export Version)

Seiko 6309-7040 Turtle: May 1981 Export Cushion Diver (Fully Serviced)

This Seiko 6309-7040 Turtle is fully serviced by our watchmaker in Japan, with all functions working perfectly — the export cushion-case diver with a matte black dial, Roman/English day-date, an amazing Hardlex crystal, and honest tool-watch wear on the case and bezel. Caseback 6309-7040, serial 153963 (May 1981). Ships on an aftermarket Seiko rubber strap as photographed.

Seiko 6309 Turtle — the export sibling of the 6306

From 1976 Seiko’s Turtle line split by market. The 6306 stayed JDM: Calibre 6306A (typically 21 jewels, hacking) with the bilingual Kanji/English day wheel. The 6309 is the export counterpart — same iconic cushion case and 150 m diver DNA, but Calibre 6309A (17 jewels, non-hacking) with a day disc built for overseas markets. This example shows a Roman / English day wheel at three, not Kanji. Same Turtle silhouette the modern Prospex line still echoes.

This Seiko 6309-7040 (May 1981 · matte black)

Published size: 45 mm across, 48 mm lug-to-lug, 13 mm thick, 22 mm between the lugs. Dial code: JAPAN 6309-704L T with Suwa mark; orange-toned WATER 150m RESIST; oversized lume plots and Turtle diver hands with matching creamy patina. Screw-down crown at four; tsunami-wave screw-back. Original black bezel insert with heavy honest ghosting — tool history, not a refinished face. Ships on an aftermarket Seiko rubber strap with SEIKO-stamped buckle as photographed — no strap pairing on this listing.

Seiko 6309-7040 condition & what you receive

A strong everyday Turtle. The stainless cushion case shows only minor usage marks — hairlines and soft tool wear, geometry retained. The crystal is in amazing condition, so the matte black dial stays sharp. The bezel insert carries authentic ghosting and flea-bites; overall good for a decades-old tool diver. It has been fully serviced by our watchmaker in Japan, and all functions are working perfectly.

Read more about vintage Seiko divers (incl. the Turtle)

Want the longer story of Seiko’s diver line — including how the 6306/6309 Turtle sits beside the 6105 and Silverwave? We wrote it up on the blog.

Read the Vintage Seiko Diver Guide

Specification:

Maker: Seiko (Suwa · export Turtle)

Model: Seiko 6309-7040 Turtle (cushion case · dial code 6309-704L T)

Era: 1981 May (caseback serial 153963)

Case Diameter: 45 mm

Lug to Lug: 48 mm

Thickness: 13 mm

Lug Width: 22 mm

Case Condition: Minor usage marks · original cushion geometry retained · screw-down crown at 4 · tsunami screw-back

Dial Condition: Matte black · aged creamy lume · orange WATER 150m RESIST · Roman/English day-date · Suwa mark

Crystal: Amazing condition Hardlex

Bezel: Original black insert with honest ghosting / flea-bites

Movement: Cal. 6309A automatic (17 jewels, 21,600 bph, day-date, non-hacking) — fully serviced by our watchmaker in Japan; all functions working perfectly

Strap / Accessories: Aftermarket Seiko rubber strap · SEIKO / ST. STEEL-F buckle (as photographed)

A May 1981 export 6309-7040 Turtle — matte black dial, Roman/English day, amazing crystal, minor case marks with honest bezel wear, and a full service by our watchmaker in Japan.