Longines Spirit - 42mm - Silver

COSC (Contrôle Officiel Suisse des Chronomètres) certification means the watch movement has undergone rigorous independent testing for accuracy under various conditions (temperature, positions) and meets specific high standards for precision.

The power reserve is built into the mainspring. To maintain it, ensure the watch is worn daily for at least 8-10 hours or manually wound periodically if not worn regularly. If the watch stops, wind it fully.

Yes, the black ceramic insert on the bi-directional bezel is functional and can be used for timing events. It is also highly scratch-resistant.

The watch has 100-meter water resistance, making it suitable for splashes and rain. However, it is not designed for prolonged underwater activities such as swimming or scuba diving. Avoid pressing the crown while underwater.

Longines generally recommends a service every 5-7 years to ensure optimal performance and longevity of the movement. Regular care and avoiding extreme conditions can extend service intervals.

The watch features a scratch-resistant sapphire crystal with an anti-reflective coating on both sides for enhanced clarity and durability.

The watch may have run out of power. Manually wind the crown clockwise 30-40 times. If it continues to stop, it may require servicing.

Ensure the watch is not exposed to strong magnetic fields. If the issue persists, the COSC certification indicates high accuracy; it may need to be checked by a watchmaker.

Ensure the time is not set between 9 PM and 3 AM when adjusting the date. Always set the date when the watch is showing AM hours (e.g., 10:00 AM) to prevent the date from jumping incorrectly.

Ensure you are turning or pulling the crown gently and straight. If it feels stuck, do not force it, as this could damage the movement. Contact an authorized service center.