Tissot · Seastar 1000 and Seastar 1000
Tissot T1204171104103 vs Tissot T1208071105100
14 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 | 316L stainless steel, 45.50 mm, with screw-down crown and caseback | 316L stainless steel, 40.00 mm, with screw-down crown and caseback |
| Diameter | 45.5 mm | 40 mm |
| Thickness | 12.82 mm | 12.48 mm |
| Lug to lug | 45.5 mm | 40 mm |
| Lug width | 22 mm | 20 mm |
| Water resistance | Water-resistant up to a pressure of 30 bar (300 m / 1000 ft) with screw-down crown and push-buttons | Water-resistant up to a pressure of 30 bar (300 m / 1000 ft) with screw-down crown |
| Crystal | Sapphire with double antireflective coating on top and bottom sides | Sapphire with one antireflective coating on bottom side |
| Bezel | Stainless steel with aluminium bezel ring, anti-clockwise rotating, with Super-LumiNova on the case | 316L stainless steel with mineral ring, anti-clockwise rotating, with Super-LumiNova on the case |
| Dial | Blue, with index markers and Super-LumiNova on the hands | Black, with index markers and Super-LumiNova on the hands |
| Case back | Screw-down caseback | Screw-down and see-through caseback |
| Bracelet | Stainless steel, reference T605046894, interchangeable quick release | Stainless steel, reference T605049459, interchangeable quick release |
| Clasp | Folding clasp with safety lock, diver extension and double push-buttons | Folding clasp with safety lock and push-buttons |
| Movement | Quartz chronograph PowerDrive | Swiss automatic |
| Movement notes | Battery voltage 1.55 volts. EOL battery end-of-life indicator, 30-minute and 1/10 second counters, central 60-second chronograph hand, ADD and SPLIT functions. Date. Total weight 180.00 g. Country of manufacture given as Switzerland, with a stated two-year warranty. | 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.
- Crown
- Screw-down
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.
| Power reserve | not stated | 80 hours |
|---|
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 45.5 mm on the T1204171104103 against 40 mm on the T1208071105100 — a 5.5 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 T1204171104103, and put the figure in the listing rather than the diameter alone.
These reach different buyers
45.5 mm on the T1204171104103 against 40 mm on the T1208071105100. Diameter is a poor predictor of how a watch actually sits, but it is the field buyers filter on, so the two land in front of different people. Do not let one listing's photographs or copy stand in for the other.
Two different ownership conversations
The T1204171104103 is quartz and the T1208071105100 is self-winding. That changes what a buyer needs telling at handover, and it changes intake: a hand-wound watch has no rotor to mask a tired mainspring, and a stopped quartz watch is usually a battery rather than a fault.
What to check on each
T1204171104103
- Unscrew both pushers before testing the chronograph. Tissot states the 30 bar rating with screw-down crown and push-buttons, so the pushers thread down and will not operate until released.
- Grade the bezel ring as aluminium. It dulls, fades and takes dents rather than chipping, and a faded insert on this reference is honest wear rather than damage.
- Exercise the ADD and SPLIT functions separately. Both are listed for this movement and a split that will not catch up to the running time is a fault a simple start-stop test misses.
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
- Tissot official product page for reference T1204171104103 (Tissot Seastar 1000 45.5mm) - SKU: T1204171104103; Weight (g): 180.00; Warranty: 2 Years of Warranty; Country of manufacture: Switzerland; Length (mm): 45.50; Width (mm): 45.50; Thickness (mm): 12.82; Lug width (mm): 22.00; Water resistance: Water-resistant up to a pressure of 30 bar (300 m / 1000 ft) with screw-down crown and push-buttons; Case material: 316L stainless steel; Case options: aluminum bezel ring, Anti-clockwise rotating bezel, Screw-down crown and caseback; Bezel Material: Stainless steel; Luminescent material on case; Super-LumiNova; Crystal: Sapphire with double antireflective coating on top and bottom sides; Movement: Quartz chronograph PowerDrive; Battery voltage (volts); 1.55; Functions: EOL (battery end-of-life indicator), 30-minutes and 1/10 of a second counters, Central 60-seconds chronograph hand, ADD and SPLIT functions; Main Functions: Date; Dial colour: Blue; Indexes: Index; Luminescent material on the hands: Super-LumiNova; Strap/Bracelet reference: T605046894; Strap material: Stainless steel; Strap colour: Grey; Buckle: Folding clasp with safety lock, diver extension and double push-buttons; Bracelet option: Interchangeable quick release bracelet — 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 Tissot. Specifications are read from each manufacturer's own published documentation on the dates shown and may change; the manufacturer's current documentation governs.