Short answer: a replica Fifty Fathoms 5015 with a tritium dial is a 45 mm copy of Blancpain's modern automatic diver, finished with warm beige luminous paint that mimics the look of aged tritium. None of it is radioactive. Real tritium paste left watch production in the late 1990s, so every tritium-style replica uses inert Super-LumiNova or a pigment blend tuned to the same faded color. Judge the watch on case size, bezel action, dial printing, and movement behavior. The lume label is a cosmetic detail, not a spec sheet.

Before You Order

  • Measure your wrist. A 45 mm case with a thick profile suits wrists from roughly 7 inches up.
  • Set a budget and learn what movement class it buys, from a plain Asian automatic to a Swiss-grade clone.
  • Pick the dial tone you want: pale cream, deep tan, or orange-brown patina.
  • Plan for service. A replica automatic often needs regulation within the first year.
  • Accept that a replica has no resale value and cannot pass as genuine.

What "Tritium" Means on the 5015

Tritium is a radioactive isotope of hydrogen. Watchmakers mixed it into luminous paint from the 1960s onward because it glowed on its own, with no need to charge under light. A dial marked "T SWISS MADE T" comes from that period. The glow faded as the isotope decayed, and the paint shifted from white to cream, then to brown or orange. Radiation rules in the late 1990s pushed brands to non-radioactive lume, and Super-LumiNova took over, which is why new dials carry a plain "SWISS MADE" marking.

A replica sold as tritium copies the second half of that story: the aged color. It cannot copy the first half, because the paint does not glow on its own and holds little charge. Treat it as a warm dial tone, and look at it under a lamp before you commit.

How to Inspect a Replica 5015 Tritium Dial

  1. Measure the case across the bezel and through the caseback with calipers. A listed 45 mm should read within a millimeter of that.
  2. Turn the bezel a full circle. It should move with firm clicks, stop at each marker, and hold. The triangle pip at 12 must line up with the dial.
  3. Study the crystal at an angle. A domed sapphire with inner anti-reflective coating stays clear; cheap glass shows a blue haze.
  4. Inspect the dial text with a 10x loupe. "BLANCPAIN" and "FIFTY FATHOMS" should sit centered, level, and in the correct font weight, with no double printing.
  5. Compare the lume on the hands with the lume on the hour markers. They should match in tone. Patina sprayed only on the dial leaves the hands pale.
  6. Check the date window and wheel. The numerals should sit centered and match the dial print; a date that sits high or low signals a misaligned dial.
  7. Flip the watch and study the caseback. Engraving should be crisp and deep. Look for burrs around the lugs and a crown that screws down with no grit.
  8. Run it for a week. Note the daily rate against a phone clock, then leave it off the wrist and time how long it keeps going.

Setting and Daily Wear

  1. Wind the crown 25 to 30 turns before the first wear to top up the mainspring.
  2. Pull the crown to the time-setting position and move the hands forward until the date flips over.
  3. Set the date only after the hands are clear of the change zone, away from late evening hours.
  4. Push the crown in and screw it down until it seats. Stop as soon as you feel resistance.
  5. Log the daily rate for two weeks, then have a watchmaker regulate it if it drifts past 15 seconds a day.

Water and Lume Care

Treat water as a risk unless the watch has paperwork. Gaskets are the first part to fail on a replica, and a pressure test at a local shop tells you more than any listing text.

  • Skip swimming and showers until the case passes a pressure test.
  • Rinse the case with fresh water after contact with sweat or salt, then dry it with a soft cloth.
  • Charge the lume with a flashlight for photos, and expect the glow to fade inside an hour. Aged-tone paint holds less light than bright white lume.
  • Keep the watch away from speakers, magnets, and laptop lids.
  • Store it on a soft pad or in a case to protect the bezel insert and crystal.

Red Flags That Mean Return It

  • Dial text that sits crooked or uses a wrong letterform.
  • Lume tone that differs between hands and markers.
  • A bezel that spins with no clicks or stops short of 12.
  • A date that sits off-center or shifts when you tap the case.
  • Rotor noise that sounds like a coin in a can.
  • Seller photos that avoid the caseback or repeat the same stock shot.

Bottom line: the tritium dial is a style choice, and the watch around it decides whether you keep it. Spend your first hour with calipers, a loupe, and a clock, not with the sales page.