Reference Number
Reference number is the model identifier defined by the brand — encoding size, material, dial colour, bezel. Rolex 126610LN = Submariner 41mm steel black bezel; 126610LV = green; Patek 5711/1A = Nautilus steel bracelet; AP 15500ST = Royal Oak 15500 steel. Different from serial — reference identifies the model, serial identifies the specific watch.
Reference structure
Rolex (6-digit + suffix)
Format: XXYYYY-Z
| Position | Meaning | Example |
|---|---|---|
| 1–2 | Model family | 12 = modern Submariner/GMT, 11 = previous gen |
| 3–4 | Size + bezel | 66 = 41mm steel, 67 = 36mm |
| 5–6 | Variant | 10 = standard, 18 = blue, 19 = Hulk |
| Suffix | Bezel/dial detail | LN = black, LV = green, BLNR = blue/black, BLRO = blue/red |
Examples:
- 126610LN = Submariner 41mm steel black bezel
- 126610LV = Submariner 41mm steel green bezel "Starbucks"
- 126618LB = Submariner 41mm yellow gold blue dial
- 126710BLNR = GMT-Master II 40mm steel Batman
- 126710BLRO = GMT-Master II 40mm steel Pepsi
Patek Philippe (4-5 digit + suffix)
Format: XXXX/YY
Examples:
- 5711/1A = Nautilus, version 1A (integrated steel bracelet)
- 5711/1G = Nautilus white gold
- 5711/1R = Nautilus rose gold
- 5167A = Aquanaut steel
- 5227G = Calatrava white gold
AP (5-digit + suffix)
Format: NNNNN.YY.A.NNN.YY.NN
Examples:
- 15500ST.OO.1220ST.01 = Royal Oak 15500 steel
- 15500OR.OO.1220OR.01 = Royal Oak 15500 rose gold
- 15400ST = Royal Oak 15400 (predecessor)
- 26420SO.OO.A002CA.01 = Royal Oak Offshore 26420
Omega
Format: 310.30.42.50.01.001
Examples:
- 310.30.42.50.01.001 = Speedmaster Moonwatch 42mm
- 210.30.42.20.03.001 = Seamaster 300M 42mm
- 220.10.41.21.10.001 = Aqua Terra 41mm
Why reference matters
1. Precise model ID
Dealers price by reference, not by "Submariner" alone — price varies sharply within the same family.
2. Serial cross-check
- Serial tells year of production
- Reference tells model variant
- Both must match the warranty card
3. Frankenwatch detection
- Caliber number on movement must match reference
- 126610LN requires caliber 3235 (not 3135 of the predecessor)
Rolex suffix decoder
Bezel colour
- LN = Lunette Noire (black)
- LV = Lunette Verte (green)
- LB = Lunette Bleue (blue)
- CHNR = Black/brown "Root Beer"
Multi-colour bezel
- BLNR = Bleu/Noir (Batman)
- BLRO = Bleu/Rouge (Pepsi)
- BLBR = Bleu/Brun
Material
- No suffix = steel
- ST = Steel (AP convention)
- YG = Yellow Gold
- RG / OR = Rose Gold / Or Rose
- WG / OG = White Gold
Transitional reference
Rolex occasionally produced intermediate references with mixed-generation features — called transitional references — collectors prize them with premium.
Examples:
- Submariner 16800 (transitional before 16610)
- GMT-Master 16750 (transitional before 16710)
Recommendations
Pre-owned buyers
- Verify reference on case + warranty card matches
- Search the reference on WatchCharts or Chrono24 for market pricing
- Confirm caliber matches reference generation
Sellers
- State the reference when sending photos — quote accuracy improves
- Use correct suffix (LN vs LV is a meaningful price difference)
Send watch + reference number via LINE — 10-minute valuation.
Sources: Rolex reference number guide · Patek Philippe reference structure · AP reference matrix