Short answer
There is no catalogued IWC reference called IW93879. IWC uses the letters IW followed by a set of digits, and every model the brand sells can be looked up in its own listings. A watch sold as an "IW93879" is a replica, a fantasy build, or a mislabeled hybrid that borrows parts from two or three models. You cannot verify it against a factory catalog, so the only thing you can grade is the physical watch in front of you. Use the checks below in order and you will know within ten minutes whether the piece is worth the asking price.
Why the reference number matters
Sellers use invented numbers for two reasons. First, a number that does not exist cannot be compared against a genuine sample, which makes it harder for a buyer to spot errors. Second, a fantasy reference lets a seller mix features from different lines, such as a pilot dial in a dress case, without anyone calling it wrong. Treat the number as a warning sign, not as proof of anything. Ask which real model the build copies, and if the seller cannot name one, move to the next listing.
Grading checklist
- Request a clear photo of the case back with the reference, serial, and any engraving visible in one frame.
- Compare that engraving with photos of the genuine model the seller claims it copies.
- Ask for the case diameter and lug width in millimeters, then measure against the stated size.
- Request a short video of the second hand sweeping under a light source.
- Ask which movement is inside and whether it is automatic, hand wound, or quartz.
- Ask for the power reserve figure and the beat rate in vibrations per hour.
- Request side profile photos of the case and bracelet to check thickness and finishing.
- Ask for the water resistance rating and whether it was pressure tested.
- Compare the quoted price against the range for that tier of replica.
- Confirm the return window and payment method before you send money.
Movement checks
A cheap build hides a quartz or low grade automatic inside a decorated case back. A quartz watch shows a ticking second hand that jumps once per second. A genuine-style automatic sweeps in several small steps per second, and a high beat movement shows eight ticks per second at 28,800 vibrations per hour. Ask for the beat rate in numbers, not adjectives. If the seller cannot answer, the movement is the reason.
Case and bracelet checks
Look at the lug edges, the crown guards, and the gap between the end links and the case. Sharp, unfinished edges and uneven gaps point to a low tier build. On a better replica the brushing runs in one direction, the polished bevels are crisp, and the crown turns without grit. Ask for the weight in grams. A steel case that feels light for its size usually means a thin case tube and a hollow bracelet.
Dial, hands, and crystal
Print quality decides whether the watch reads as cheap from arm's length. Check the alignment of the markers with the chapter ring, the thickness of the font, and the finish on the applied indices. Ask for a photo taken at an angle so you can see the anti-reflective coating on the crystal. A blue or purple wash across the dial means a coated sapphire. No wash at all usually means mineral glass.
Price signals
Replica pricing splits into tiers based on movement, case finishing, and dial work. A price far below the normal range for that tier means a quartz movement, a plated case, or a stock photo that does not match the watch shipped. A price far above the range is a markup with no hardware behind it. Ask what the price includes, and treat free shipping as a cost already built into the number.
Questions to ask before you pay
- Which genuine model is this build based on?
- What movement is inside, and what is its beat rate?
- Can you send photos of the actual watch, not stock images?
- What is the return window and who pays return shipping?
- Is the case solid steel or plated?
- What is the water resistance rating?