Seiko against Tissot
Seiko SPB317J1 vs Tissot T1208071105100
13 published specifications differ between these two, and 1 are identical. Every figure below is what the manufacturer states for that reference; nothing is inferred from the other watch.
What differs
| Specification | Tissot Seastar 1000 40mm Powermatic 80, black dialT1208071105100 | |
|---|---|---|
| Case | Stainless steel, 41.0 mm | 316L stainless steel, 40.00 mm, with screw-down crown and caseback |
| Diameter | 41 mm | 40 mm |
| Thickness | 12.3 mm | 12.48 mm |
| Lug to lug | 46.9 mm | 40 mm |
| Water resistance | 200m / 660ft diver's | Water-resistant up to a pressure of 30 bar (300 m / 1000 ft) with screw-down crown |
| Crystal | Curved sapphire crystal, anti-reflective coating on inner surface | Sapphire with one antireflective coating on bottom side |
| Bezel | Unidirectional rotating bezel | 316L stainless steel with mineral ring, anti-clockwise rotating, with Super-LumiNova on the case |
| Case back | Screw case back | Screw-down and see-through caseback |
| Crown | Screw-down crown | Screw-down |
| Bracelet | Silicone band, 20 mm between the lugs | Stainless steel, reference T605049459, interchangeable quick release |
| Movement | Automatic with manual winding | Swiss automatic |
| Power reserve | Approximately 70 hours | 80 hours |
| Movement notes | Precision stated as +25 to −15 seconds per day. Stop second hand and date display. Magnetic resistance 4,800 A/m. LumiBrite on hands, indexes and bezel. Total weight 100.0 g. | Patented Nivachron balance spring. Date. Total weight 148.00 g. Country of manufacture given as Switzerland, with a stated two-year warranty. Tissot does not name a calibre on this page. |
What is identical
Worth knowing as much as the differences: these are the specifications you cannot use to tell the two apart.
- Lug width
- 20 mm
Stated for one, not the other
These rows cannot be compared, because one maker publishes the figure and the other does not. An empty cell is a gap in the manufacturer's documentation, not a gap in the watch — and not a licence to fill it in from the other column.
| Dial | not stated | Black, with index markers and Super-LumiNova on the hands |
|---|---|---|
| Clasp | not stated | Folding clasp with safety lock and push-buttons |
| Calibre | 6R35 | not stated |
| Jewels | 24 | not stated |
What the differences cost you
Each note below follows from the published figures in the tables above — what they mean for intake, for a listing, and for the handover. Nothing here estimates a price or a margin.
One of these is the harder fit
Lug to lug is 46.9 mm on the SPB317J1 against 40 mm on the T1208071105100 — a 6.9 mm difference across the wrist. Diameter is what buyers ask about; lug to lug is what decides whether a case sits flat or overhangs. Ask for a wrist measurement before shipping the SPB317J1, and put the figure in the listing rather than the diameter alone.
Do not describe these the same way
300 metres on the T1208071105100 against 200 on the SPB317J1. Both are more than daily life asks for, so the number is a listing-accuracy question rather than a practical one: quote each watch its own figure, and remember that neither rating survives an unserviced case by itself.
What to check on each
SPB317J1
- Bend the silicone band fully back on itself at both lug ends and look into the crease. Silicone fails from inside a fold, and a flat inspection will miss cracking that is about to become a failure.
- Confirm the calibre is the 6R35 rather than the 6R55 used elsewhere in this family. Both are 24-jewel automatics from the same maker, and they carry different reserves.
- Weigh it against the published 100 grams. That is remarkably light for a steel 200-metre diver and is largely the band rather than the case, which matters if a buyer intends to fit a bracelet.
T1208071105100
- Grade the bezel ring as mineral. Tissot specifies a mineral bezel ring here, which scratches in a way ceramic and sapphire inserts do not, so surface marking is expected wear rather than a defect.
- Confirm the bezel turns anti-clockwise only. Tissot describes it as anti-clockwise rotating, so any clockwise movement at all is a failure of the safety design.
- Thread and unthread both the crown and the caseback if you can. This reference specifies screw-down on both, and the published 30 bar rating is stated as conditional on the screw-down crown.
Sources
- Seiko official product page for reference SPB317J1 (Prospex Sea) - Caliber Number: 6R35; Movement Type: Automatic with manual winding; Precision: +25 to -15 seconds per day; Power reserve: Approx. 70 hours; Jewels: 24; Case Material: Stainless steel; Case Size: Thickness:12.3mm; Diameter:41.0mm; Lug-to-lug:46.9mm; Crystal: Curved sapphire crystal; Crystal Coating: Anti-reflective coating on inner surface; LumiBrite: LumiBrite on hands, index(es) and bezel; Band Material: Silicone; Distance between lugs: 20; Water Resistance: 200m / 660ft diver's; Magnetic Resistance: 4,800 A/m; Weight: 100.0g; Functions: Stop second hand function; Date display; Features: Unidirectional rotating bezel; Screw-down crown; Screw case back — retrieved 2026-09-22
- Tissot official product page for reference T1208071105100 (Tissot Seastar 1000 40mm) - SKU: T1208071105100; Weight (g): 148.00; Warranty: 2 Years of Warranty; Country of manufacture: Switzerland; Length (mm): 40.00; Width (mm): 40.00; Thickness (mm): 12.48; Lug width (mm): 20.00; Water resistance: Water-resistant up to a pressure of 30 bar (300 m / 1000 ft) with screw-down crown; Case material: 316L stainless steel; Case options: Mineral bezel ring, Anti-clockwise rotating bezel, Screw-down crown and caseback, See-through caseback; Bezel Material: 316L stainless steel with mineral; Luminescent material on case; Super-LumiNova; Crystal: Sapphire with one antireflective coating on bottom side; Movement: Swiss automatic; Power reserve (hours): 80; Functions: Patented Nivachron balance spring; Main Functions: Date; Dial colour: Black; Indexes: Index; Luminescent material on the hands: Super-LumiNova; Strap/Bracelet reference: T605049459; Strap material: Stainless steel; Strap colour: Grey; Buckle: Folding clasp with safety lock and push-buttons; Bracelet option: Interchangeable quick release bracelet — retrieved 2026-09-22
Not affiliated with Seiko or Tissot. Specifications are read from each manufacturer's own published documentation on the dates shown and may change; the manufacturer's current documentation governs.