Tissot · PRX and PRX

Tissot T1372071109100 vs Tissot T1374071109100

6 published specifications differ between these two, and 9 are identical. Every figure below is what the manufacturer states for that reference; nothing is inferred from the other watch.

What differs

Specification	Tissot PRX 35mm Powermatic 80, green dialT1372071109100	Tissot PRX 40mm Powermatic 80, green dialT1374071109100
Case	316L stainless steel, 35.00 mm wide by 35.00 mm long	316L stainless steel, 40.00 mm wide by 39.50 mm long
Diameter	35 mm	40 mm
Lug to lug	35 mm	39.5 mm
Lug width	11 mm	12 mm
Bracelet	Stainless steel, reference T605047605, interchangeable quick release	Stainless steel, reference T605046447, interchangeable quick release
Movement notes	Patented Nivachron balance spring. Date. Total weight 104.00 g. Country of manufacture given as Switzerland, with a stated two-year warranty. Tissot does not name a calibre on this page.	Patented Nivachron balance spring. Date. Total weight 138.00 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.

Thickness: 10.93 mm
Water resistance: Water-resistant up to a pressure of 10 bar (100 m / 330 ft)
Crystal: Sapphire with one antireflective coating on bottom side
Bezel: Stainless steel
Dial: Green, with index markers and Super-LumiNova on the hands
Case back: See-through caseback
Clasp: Butterfly clasp with push-buttons
Movement: Swiss automatic
Power reserve: 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 39.5 mm on the T1374071109100 against 35 mm on the T1372071109100 — a 4.5 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 T1374071109100, and put the figure in the listing rather than the diameter alone.

These reach different buyers

40 mm on the T1374071109100 against 35 mm on the T1372071109100. 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.

What to check on each

T1372071109100

Check the bracelet reference is T605047605 and not the T605046447 fitted to the 40 mm. The two sizes take different bracelets and a mismatched one will not meet the case cleanly.
Measure the case before you describe it. Tissot publishes 35.00 mm in both directions here, where the 40 mm reference is 40.00 wide by 39.50 long, so this one is genuinely square.
Weigh it against the published 104 g. That is thirty-four grams lighter than the 40 mm, which is most of what a buyer choosing between the two will actually feel.

T1374071109100

Treat the bracelet as part of the case. At a published 12 mm lug width on a 40 mm watch, this is an integrated design and a damaged or missing bracelet is not solved by fitting a strap from the drawer.
Record the bracelet reference T605046447 and check it against the watch. Bracelets are model-specific here and a bracelet from another PRX will not sit correctly.
Work the butterfly clasp repeatedly and check both sides latch. A butterfly clasp hides its mechanism inside the bracelet, so it is rarely inspected and its springs carry the whole weight.

Sources

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.