The 43mm Blancpain Fifty Fathoms is the Bathyscaphe, reference 5000. Blancpain lists the three-hand Bathyscaphe at 43.00mm. The Fifty Fathoms Automatique is 45mm. The 2024 Fifty Fathoms is 42.3mm. A fake 43mm Fifty Fathoms copies the Bathyscaphe. It does not copy the Automatique. No replica uses the Blancpain calibre 1315.
Genuine 43mm specs to compare
- Case diameter: 43.00mm
- Case thickness: 13.83mm
- Case material: steel or titanium
- Water resistance: 300m
- Movement: calibre 1315, automatic, 227 parts, 35 jewels, 28,800 vph
- Power reserve: 120 hours from three series-coupled barrels
- Balance spring: silicon
- Bezel: unidirectional, ceramic insert
- Crystal: sapphire, antireflective coating on both faces
- Strap options: sailcloth, rubber, NATO, alligator
Blancpain's US list price for a steel Bathyscaphe three-hand sits near $15,000. Prices change. Ask a dealer for the current figure.
Checks that separate a replica from the real watch
- Caseback text. Look at the depth and edge sharpness of the engraving. Compare it to a factory photo of the reference.
- Winding rotor. The calibre 1315 rotor carries finished engraving. Printed text on a plain disc points to a copy.
- Date font and window position. Compare both to images of the reference.
- Bezel action. A real bezel turns with firm detents and no side play.
- Crown threads. Check for smooth engagement. Stripped threads show up on fakes after a few months of use.
- Lume. Real markers glow even across the dial and fade over hours.
- Thickness. Put the watch on a caliper. Measure the case, not the seller's ad copy.
What runs inside the fakes
Most 43mm Fifty Fathoms replicas use an Asian automatic in the ETA 2824 or 2836 family, or a Miyota 9015. Some carry a decorative plate that copies the 1315 layout. None of these movements deliver a 120-hour reserve. Power reserve on those calibers runs about 38 to 42 hours.
You can test this. Wind the watch full. Set it down. Note the time it stops. A stop near 40 hours confirms a third-party movement. A 1315 runs five days.
Price signals
Replica prices for a 43mm Fifty Fathoms run from about $80 to $500. Sellers quote factory names. Factory names change, and one name can cover several batches. No replica carries a Blancpain warranty. No Blancpain service center will touch one.
US legal points
Trafficking in counterfeit goods is a federal crime under 18 U.S.C. 2320. Penalties include prison terms and fines. US Customs and Border Protection can seize counterfeit watches at import under 19 U.S.C. 1526. A buyer also faces civil claims from the trademark owner. In practice, enforcement targets sellers and importers more than single buyers. That is not a guarantee.
What is not known
Batch quality moves. No seller publishes pressure test data. Treat any replica as not waterproof, no matter what the dial says. Have a watchmaker pressure test the case before you swim with it.