Q: What is the Omega Seamaster 300 41mm Master Co‑Axial?
A: It’s a classic, professional dive watch in stainless steel with a 41mm case, black dial with vintage‑style markers, a unidirectional black ceramic bezel, and a transparent case back. This listing is a full set with original box and papers.

Q: Is it water‑resistant and can I swim or dive with it?
A: The Seamaster 300 was originally rated to 300 metres. As a pre‑owned piece, water resistance cannot be guaranteed without recent servicing and pressure testing. For swimming or diving, have the gaskets checked/replaced and the watch pressure‑tested, and always ensure the crown is fully screwed down. Avoid hot showers/saunas and rinse with fresh water after saltwater use.

Q: Which movement does it use and what’s the power reserve?
A: It houses an OMEGA Master Co‑Axial automatic movement, celebrated for durability and anti‑magnetic performance. The typical power reserve for this family is around 60 hours. This model is time‑only (no date) and features hacking seconds for precise setting.

Q: Is it anti‑magnetic and how does that help?
A: Yes—OMEGA’s Master Co‑Axial movements use non‑ferrous components to resist strong magnetic fields (commonly cited at over 15,000 gauss), helping maintain accuracy in everyday magnetic environments such as laptops, bags with magnetic clasps and speakers.

Q: What materials are used for the bezel and crystal?
A: The Seamaster 300 features a scratch‑resistant sapphire crystal and a unidirectional ceramic bezel designed for timing elapsed minutes underwater. The dial and bezel have luminous elements for legibility in low light.

Q: How do I wind and set the time?
A: Unscrew the crown anti‑clockwise. Position 1: manual wind (20–40 turns if the watch has stopped). Position 2: set the time; the seconds hand will stop for precise setting. When finished, push the crown in and screw it down firmly to help maintain water resistance.

Q: Will the bracelet fit my wrist, and can it be resized?
A: The bracelet length is approximately 21 cm. We can size the bracelet prior to dispatch, and additional links may be sourced subject to availability. The lug width is typically 21 mm, so straps should match this size; we’re happy to advise on compatible Omega straps or alternatives.

Q: How does the Seamaster 300 differ from the Seamaster Diver 300M?
A: The Seamaster 300 leans into a vintage‑inspired aesthetic with a clean, time‑only dial and no helium escape valve. The Diver 300M has a more modern look, often with a date, wave dial and helium escape valve. Both are rated to 300 metres, but styling and features differ.

Q: What servicing and accuracy should I expect?
A: Performance varies with age and service history. A routine service every 5–10 years is generally recommended, or sooner if you notice issues (e.g., running fast/slow, moisture). Keep the watch away from extreme magnets and chemicals, and wipe it with a soft microfibre cloth after wear.

Q: What is included, and do you offer authenticity and warranty?
A: This listing is delivered as a full set with original box and papers. A Retro Tale rigorously authenticates every item and guarantees 100% originality. All watches include a 12‑month mechanical guarantee. We offer free, fully insured DHL shipping, a 14‑day return policy, and 0% customs fees for EU buyers; contact us for any specific delivery or warranty questions.