If you are hunting a fake IWC Aquatimer Deep Time, fix the name first. IWC never built a watch called the Deep Time. Buyers usually mean the Aquatimer Deep Two (2009, ref IW354701) or the Aquatimer Deep Three (2014, ref IW355701). Both are titanium dive watches with a mechanical depth gauge, and both get faked. Here is the short answer: replicas of these two exist, they photograph well, and as far as I can tell none of them has a working depth gauge. That missing function is most of the watch.
What the genuine Deep Two and Deep Three actually do
The trick lives in the caseback. A sealed membrane sits behind a small aperture, water pressure pushes it inward, and that movement drives a hand on the dial so you can read your current depth on the way down. A second hand in red parks at your deepest point and stays there until you reset it, which is how you track maximum depth without staring at the dial. The scale reads to 50 m. Water resistance is roughly 100 m, modest for a dive watch but fine, since the gauge is the reason the thing exists. The Deep Two runs on the calibre 30110, the Deep Three on a modified 30120. Both are discontinued, so genuine examples now sell for many times any replica price.
Why the gauge is the part factories cannot clone
A pressure gauge needs a calibrated spring, a sealed opening in the caseback, and a hand that moves smoothly under load without letting water past the seal afterward. That is a real engineering problem, and solving it costs real money. A workshop can copy a dial, a case, and a bracelet in a few weeks. It cannot build a pressure transducer into a $400 watch and stay in business.
What the fakes do instead
- A static depth hand, usually glued or press-fit onto a decorative subdial.
- A max-depth hand that moves when you turn a crown instead of when water pushes a membrane. Often it does not move at all.
- A steel case finished to look like titanium. Noticeably heavier in the hand.
- A flat stamped caseback with no membrane recess.
- Depth scale printed a hair off, or "AQUATIMER" lettered too thick for the dial.
- Loose or gritty bezel action. The genuine SafeDive bezel has a firm, defined click.
How I would check one in person
- Weigh it against a known titanium watch. Titanium feels almost toy-like for its size. Steel does not.
- Turn the crown and watch the max-depth hand. On a real one it snaps back with a crisp reset. On a fake it drifts or does nothing.
- Flip it over. Look for the membrane housing, not a stamped medallion.
- Check the crown threads. Cheap reps feel sandy after two turns.
- Charge the lume with a phone light, then step into a closet. Weak, uneven glow is common.
- Confirm the movement. No 30110 or 30120 means no gauge, no matter what the listing says.
Price and what the tier buys you
Clean 1:1 examples of these two references sit around $300 to $600. That buys a convincing case, a decent bracelet, and a readable dial. It does not buy a depth gauge, and no listing at any price does. If a seller claims a working gauge, ask for video of the hand moving as pressure changes. There is no honest way to fake that clip.
Who should skip the replica
If you dive, or if the gauge is the reason you want the watch, buy something else. A fake Aquatimer Deep is a good-looking titanium dive watch with a dead complication on the dial. That is fine if you want the look. It is a bad deal if you want the function, and the function is the whole reason this reference exists.