Seiko Prospex SPB517J1 Datsun 240Z Speedtimer
The SPB517J1 is Seiko’s mechanical Datsun 240Z Speedtimer, limited to 2,500 pieces. It is a 39.5 mm sports watch with a countdown ring, not a chronograph and not the solar SSC957 Datsun. If you want the rally look in a case that wears smaller than a Sumo, this is the reference.
The dial is matte black. DATSUN sits at 6, where a numeral would usually be, and the date window is just to its right, near 4:30. The seconds hand is red. Applied bars carry lume, and a thin red arc tracks the inner ring. That ring is a countdown scale. The crown at 4 o’clock turns it. The crown at 3 sets the time. They are crowns, not chronograph pushers.
Seiko lists calibre 6R55: automatic, manual wind, hacking seconds, 24 jewels, about 72 hours of reserve, and +25 to −15 seconds a day. The case is stainless steel with Seiko’s super-hard coating, 39.5 mm wide, 12.0 mm thick, and 44.5 mm lug to lug. Lug width is 20 mm. The crystal is curved sapphire with anti-reflective coating on the inner surface. Water resistance is 20 bar, which is 200 metres. Official weight is 86 g. Magnetic resistance is listed at 4,800 A/m.
What you actually get on the wrist
The strap is black cow leather, punched like a rally strap, with white stitching. Red lining shows through the holes and on the reverse. The clasp is a three-fold with a push-button release. Seiko describes the leather as coming from an LWG-certified tannery. It is not a steel bracelet. A 20 mm strap is the right replacement width.
The case back is a screw back. The gallery engraving reads LIMITED EDITION, DATSUN, JAPAN, ST.STEEL, SAPPHIRE CRYSTAL, WATER RESISTANT 20BAR, AUTOMATIC, and 6R55-00M0. It also shows 0001/2500. That 0001 figure is a catalogue sample. Seiko engraves a serial, but you do not choose the number, and the photo is not the serial of the watch we send. The dial is marked JAPAN 6R55.
Seiko’s feature list names a screw case back. It does not name a screw-down crown. Seiko Boutique lists the crown as pull-out. Do not treat this as a guarded diver crown. Two hundred metres is the water rating. The inner ring is for a countdown, not a dive timer.
The red box in the gallery carries Seiko Prospex and Datsun marks. It is the presentation box for this limited edition, not a generic Seiko carton.
Specifications
- Reference: SPB517J1, Prospex Speedtimer, Datsun 240Z limited edition
- Edition size: 2,500. Serial is engraved; the 0001/2500 photo is a sample
- Movement: Seiko 6R55, automatic with manual wind and hacking, 24 jewels
- Reserve and rate: about 72 hours; +25 to −15 seconds per day
- Case: stainless steel with super-hard coating, 39.5 mm / 12.0 mm / 44.5 mm lug-to-lug
- Lug width: 20 mm
- Crystal: curved sapphire, anti-reflective coating on the inner surface
- Water resistance: 200 metres / 20 bar
- Crowns: pull-out time crown at 3; second crown at 4 turns the countdown ring
- Case back: screw back, marked Japan
- Strap: black perforated cow leather, red lining, three-fold clasp
- Weight: 86 g on Seiko’s sheet
- Dial: matte black, DATSUN at 6, date near 4:30, red seconds
Frequently asked questions
How many SPB517J1 watches were made?
2,500. The case back is marked LIMITED EDITION and carries a serial. The gallery photo engraved 0001/2500 is a catalogue sample, not the number on the watch we send.
What movement is in the SPB517J1?
Calibre 6R55. It is an automatic with manual winding and a stop-seconds function, 24 jewels, and about 72 hours of reserve. Seiko rates it at +25 to −15 seconds per day.
Is the SPB517J1 a chronograph or a dive watch?
Neither. The second crown turns an inner countdown ring. There are no chronograph pushers. Water resistance is 200 metres and the case back screws down, but the crown is a pull-out and the ring is not a dive bezel.
How is the SPB517J1 different from the SSC957 Datsun Speedtimer?
This one is mechanical: 6R55, 39.5 mm, leather, 200 metres, DATSUN at 6, 2,500 pieces. The SSC957P1 is a solar chronograph, 41.4 mm, 100 metres, with DATSUN at 12 and a run of 4,000. Same theme, different watch.
What size strap does the SPB517J1 take?
20 mm. It ships on the perforated leather strap, not a bracelet. Lug-to-lug is 44.5 mm, so it wears smaller than a 45 mm Sumo even though the water rating is the same 200 metres.
Where can I buy the SPB517J1 in Australia?
Chronospride lists authentic stock and inspects the watch before dispatch. Eligible orders ship free Australia-wide. Covered by Chronospride’s 12 months warranty, handled by our team. See our authenticity and warranty page.
Choose the SPB517J1 if you want the mechanical Datsun Speedtimer in a 39.5 mm case. If you want a solar chronograph with DATSUN at 12, look at the SSC957 instead.
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.
| Case-Size | 39.5mm |
|---|---|
| Band-Width | 20mm |
| Lug-Width | 20mm |
| Lug to lug size | 44.5mm |
| Case Thickness | 12mm |