Seiko Prospex SPB381J1 1968 Heritage Diver GMT
Need a 42 mm Seiko diver with a second time zone? The SPB381J1 (SPB381J) reworks the 1968 cushion diver with Caliber 6R54 GMT, about 72 hours of reserve, a green dial, gold-tone 24-hour hand, and a green ceramic bezel insert. Sapphire, 200 m, screw-down crown, steel bracelet with diver’s extension.
Case diameter is 42 mm, thickness 12.9 mm, lug-to-lug 48.6 mm, lug width 20 mm. The 6R54 adds a independently settable GMT hand versus a three-hand 6R35. Date sits between 4 and 5. LumiBrite on hands, indexes, and bezel. This is regular production, not a 1,000-piece LE—priced to wear, not to sit in a box.
Why the 1968 GMT is a travel diver
42 mm is easier than a 45 mm Sumo. Ceramic bezel insert resists fading. Three-day reserve covers a weekend off the wrist. Dual time is useful for flights without buying a dedicated GMT dress watch. Chronospride inspects authentic stock before dispatch.
- Movement: Seiko 6R54 automatic GMT, manual wind, hacking, 24 jewels, about 72 hours
- Accuracy: +25 to −15 seconds per day (Seiko spec)
- Case: 42 mm, 12.9 mm thick, 48.6 mm lug-to-lug, 20 mm lugs
- Crystal: sapphire, inner AR
- Water resistance: 200 metres diver’s
- Bezel: unidirectional, ceramic insert
- Bracelet: steel, secure clasp with extender
- Weight: about 176 g
Frequently asked questions
Does the SPB381J1 have a true GMT?
Yes. Caliber 6R54 drives a 24-hour hand for a second zone against the 24-hour marks, plus local time and date.
What size is the SPB381J1?
42 mm diameter, 12.9 mm thickness, 48.6 mm lug-to-lug, 20 mm lug width.
Is it a limited edition?
No. It is a regular Prospex 1968 reinterpretation GMT. Easier to wear as a daily diver than a numbered LE.
Is 200 metres enough for diving?
Seiko rates it as a 200 m diver with screw-down crown and screw case back. Recreational diving is within spec; follow Seiko’s care notes.
What crystal does it use?
Sapphire with anti-reflective coating on the inner surface—not Hardlex.
Where can I buy the SPB381J1 in Australia?
Chronospride lists authentic stock, inspected before dispatch, with Australia-wide shipping on eligible orders.
The SPB381J1 suits travel and weekend diving in a 42 mm cushion case—not a 38 mm Seiko 5.
Buying this watch in Australia
Chronospride lists authentic stock and inspects each watch before dispatch. Eligible orders ship free Australia-wide. Covered by Chronospride’s 12 months warranty, handled by our team. Read the authenticity and warranty terms before you buy. If you need a different strap width or case size, use the specs above and our shop-by-size filters rather than guessing from photos alone.
Authentic stock, inspected before dispatch. Free shipping Australia-wide on eligible orders. Covered by Chronospride’s 12 months warranty, handled by our team. See our authenticity and warranty page.
| Brand | Seiko |
|---|---|
| Case-Size | 42mm |
| Band-Width | 20mm |
| Lug-Width | 20mm |
| Lug to lug size | 48.6mm |
| Case Thickness | 12.9mm |