OMEGA · Seamaster Aqua Terra 150M and Speedmaster Moonwatch Professional
OMEGA 220.10.41.21.01.002 vs OMEGA 310.30.42.50.01.001
11 published specifications differ between these two, and 4 are identical. Every figure below is what the manufacturer states for that reference; nothing is inferred from the other watch.
What differs
| Specification | OMEGA Aqua Terra 150M 41mm, black dial220.10.41.21.01.002 | OMEGA Speedmaster Moonwatch Professional 42mm, Hesalite310.30.42.50.01.001 |
|---|---|---|
| Case | Steel, 41 mm | Steel, 42 mm |
| Diameter | 41 mm | 42 mm |
| Thickness | 13.4 mm | 13.54 mm |
| Lug to lug | 48 mm | 47.5 mm |
| Water resistance | 15 bar (150 metres / 500 feet) | 5 bar (50 metres / 165 feet) |
| Crystal | Domed scratch-resistant sapphire crystal with anti-reflective treatment on both sides | Hesalite crystal with OMEGA logo in the centre |
| Clasp | Foldover butterfly clasp with comfort setting | Foldover clasp with comfort setting |
| Calibre | Calibre OMEGA 8900 | Calibre OMEGA 3861 |
| Movement | Self-winding movement with Co-Axial escapement, automatic winding in both directions | Manual-winding chronograph movement with Co-Axial escapement |
| Power reserve | 60 hours | 50 hours |
| Movement notes | Resistant to magnetic fields reaching 15,000 gauss. Free sprung-balance with silicon balance spring, two barrels mounted in series, and a time zone function. Rhodium-plated rotor and bridges with Geneva waves. Total product weight approximately 148 g. | Resistant to magnetic fields reaching 15,000 gauss. Free-sprung balance with silicon balance spring; rhodium-plated finish with bridges carrying straight Geneva waves. Total product weight approximately 134 g. |
What is identical
Worth knowing as much as the differences: these are the specifications you cannot use to tell the two apart.
- Lug width
- 20 mm
- Dial
- Black
- Bracelet
- Steel
- Certification
- Master Chronometer, approved by METAS
Stated for one, not the other
These rows cannot be compared, because one maker publishes the figure and the other does not. An empty cell is a gap in the manufacturer's documentation, not a gap in the watch — and not a licence to fill it in from the other column.
| Frequency | not stated | 3 Hz |
|---|
What the differences cost you
Each note below follows from the published figures in the tables above — what they mean for intake, for a listing, and for the handover. Nothing here estimates a price or a margin.
Do not describe these the same way
The 310.30.42.50.01.001 is rated to 50 metres and the 220.10.41.21.01.002 to 150. A rating is a factory figure for a new watch with fresh gaskets, not a promise about a used one — but the gap still matters in writing. Describe the 310.30.42.50.01.001 in words a buyer can act on, and do not let a template carry the 220.10.41.21.01.002's language onto it.
Two different ownership conversations
The 220.10.41.21.01.002 is self-winding and the 310.30.42.50.01.001 is hand-wound. That changes what a buyer needs telling at handover, and it changes intake: a hand-wound watch has no rotor to mask a tired mainspring, and a stopped quartz watch is usually a battery rather than a fault.
Different movements to verify and to service
The 220.10.41.21.01.002 runs the Calibre OMEGA 8900 and the 310.30.42.50.01.001 the Calibre OMEGA 3861. Two consequences at intake: the service history that is normal for one calibre is not evidence about the other, and the calibre is the check that catches a movement swapped into the wrong case. Confirm the movement matches the reference rather than assuming it from the dial.
What to check on each
220.10.41.21.01.002
- Test the time zone function properly: the hour hand should jump independently in one-hour steps without disturbing the minutes or seconds. A hand that drags the minute hand with it is a fault, not a quirk.
- Check the anti-reflective coating on both crystal surfaces. OMEGA specifies treatment on both sides, and worn or patchy coating on the inner face cannot be polished away — it needs a new crystal.
- Wind and run it for a full day to confirm the 60-hour reserve behaves. Twin barrels in series should deliver consistent amplitude rather than fading early.
310.30.42.50.01.001
- Identify the crystal before anything else. Hesalite is a plastic: it scratches easily, polishes out with a cloth and compound, and carries a small OMEGA logo etched at its centre. A sapphire crystal on this case means you are looking at a different reference number.
- Do not treat scratches on a Hesalite crystal as damage in the way you would on sapphire. They are expected and largely removable, and pricing them as permanent faults misreads the material.
- Check the 3861 is what is fitted. The Moonwatch has used several calibres across its history, and the Master Chronometer 3861 is the current one — papers and caseback should agree.
Sources
- OMEGA official product page for reference 220.10.41.21.01.002 (Seamaster Aqua Terra 150M Co-Axial Master Chronometer 41 mm; steel) - Case: steel; 41 mm; Dial color: black; Crystal: domed scratch-resistant sapphire crystal with anti-reflective treatment on both sides; Water resistance: 15 bar (150 metres / 500 feet); Movement: Calibre OMEGA 8900; self-winding movement with Co-Axial escapement; certified Master Chronometer approved by METAS; resistant to magnetic fields reaching 15000 gauss; free sprung-balance with silicon balance spring; two barrels mounted in series; automatic winding in both directions; time zone function; special luxury finish with rhodium-plated rotor and bridges with Geneva waves; Power reserve: 60 hours; listed with a 5-year warranty; Re-read 2026-09-23, the page additionally publishes: Between lugs: 20 mm; Lug-to-lug: 48.00 mm; Thickness: 13.40 mm; Case diameter: 41 mm; Total product weight (approx.): 148 g; Type of Clasp: Foldover butterfly clasp with comfort setting; Bracelet material: Steel — retrieved 2026-09-23
- OMEGA official product page for reference 310.30.42.50.01.001 (Speedmaster Moonwatch Professional Co-Axial Master Chronometer Chronograph 42 mm; steel on steel) - Case: steel; 42 mm; Dial color: black; Crystal: hesalite crystal with OMEGA logo in the centre; Water resistance: 5 bar (50 metres / 165 feet); Movement: Calibre OMEGA 3861; manual-winding chronograph movement with Co-Axial escapement; certified Master Chronometer approved by METAS; resistant to magnetic fields reaching 15000 gauss; free-sprung balance with silicon balance spring; rhodium-plated finish with bridges carrying straight Geneva waves; Power reserve: 50 hours; Frequency: 3 Hz; the watch is listed with a 5-year warranty and as Swiss Made; Re-read 2026-09-23, the page additionally publishes: Between lugs: 20 mm; Lug-to-lug: 47.50 mm; Thickness: 13.54 mm; Case diameter: 42 mm; Total product weight (approx.): 134 g; Type of Clasp: Foldover clasp with comfort setting; Bracelet material: Steel — retrieved 2026-09-23
Not affiliated with OMEGA. Specifications are read from each manufacturer's own published documentation on the dates shown and may change; the manufacturer's current documentation governs.