User Manual

I. Identifying the different parts of a watch

II. How to set a Seiko Mod watch?

Screwed-in position (position 0)

The crown is fully screwed in against the case. In this position, the watch is guaranteed water-resistant up to 50 meters (see section IV for actually permitted uses).

Manual winding (position 0)

Turn the crown clockwise (turning in the other direction has no effect).

For the first setting or after a long stop, count about 25 turns for partial winding and 55 turns for full winding. Never force beyond this: the movement has a mechanical stop; unnecessary forcing will wear out the mainspring.

Setting the date (position 1)

The crown is unscrewed and pulled out to the first click (first "click").

Turn the crown clockwise or counter-clockwise depending on the model to set the date. Turning in the opposite direction manually winds the watch. The watch continues to run during this operation.

⚠️ Never do this: never set the date between 9 PM and 3 AM. During this time, the date change mechanism is already engaged in the automatic date change. Manually forcing it at this moment can irreversibly damage the gears. If necessary, first advance the hands to 6 AM, then set the date, then set the time.

Setting the time (position 2)

The crown is unscrewed and pulled out to the second click (second "click"). The second hand stops ("hacking" function), which allows the time to be set precisely to the second.

Turn the crown in either direction to adjust hours and minutes.

To avoid morning/afternoon confusion, pass the hour hand through 12 o'clock: if the date changes, it's midnight; otherwise, it's noon.

Screwing the crown back in

After each operation, carefully screw the crown back in to ensure water resistance. Return it to position 0, apply slight pressure, and screw it clockwise until you feel resistance, without forcing.

⚠️ The crown should never be unscrewed underwater or on a wet watch. This is the primary cause of water penetration into a case.

 

III. How to adjust a Seiko Mod watch bracelet (steel)

1. Tools needed

Use the small flat-head screwdriver or pin removal tool provided in your package.

2. Identify links to remove

Determine the number of links to remove. For a balanced fit, remove an equal number from each side of the clasp.

3. Identify the direction of the pins

On most bracelets, small arrows engraved on the back of the links indicate the direction in which to push the pin. Follow this direction: forcing it the wrong way will damage the link and the pin.

4. Remove pins or screws

Use the appropriate screwdriver or tool to remove the screws or pins that hold the links.

5. Remove links

Once the pins are out, remove the unwanted links.

6. Reassemble the bracelet

Replace the screws or pins in the remaining links, respecting the original direction. For screwed bracelets, a dab of thread locker (or a drop of clear nail polish) on the threads prevents them from loosening over time.

7. Check the fit

Try the bracelet on your wrist. You should be able to slip a finger between the bracelet and your skin: not too loose (risk of shock), and not too tight (discomfort, marks).

IV. Water resistance: what does "50 meters" really mean?

The water resistance standard does not correspond to an actual diving depth, but to a static test pressure. In daily use, arm movements, water temperature, and aging seals significantly reduce this resistance.

Permitted uses with 50m water resistance:

Use	Permitted
Hand washing, rain	✅ Yes
Swimming in a pool (temperate water)	✅ Yes (not recommended)
Swimming in the sea	✅ Yes (strongly not recommended, rinse with clear water afterwards)
Shower	❌ No (steam + hot water = stressed seals)
Hot bath, sauna, hammam, jacuzzi	❌ No
Scuba diving, deep freediving	❌ No
Impact water sports (water skiing, jet skiing)	❌ No

Water resistance is not permanent. Seals age, dry out, and deform. We recommend a water resistance check every 2 to 3 years, or immediately if you notice condensation under the crystal.

V. Daily use precautions

Magnetism

The NH35 movement is a mechanical movement: its internal components, especially the hairspring, are sensitive to magnetic fields.

Sources to avoid:

• Bluetooth speakers, loudspeakers, headphones
• Clasp magnets (some handbags, phone cases, cardholders)
• Induction hobs
• Tablets and iPads placed dial down on the screen
• MRI scans (remove watch imperatively)

Symptom of magnetization: the watch suddenly gains or loses several minutes a day. Demagnetization by a watchmaker (a few euros) is enough to restore it.

Shocks

The NH35 is known for its robustness, but it remains a mechanical assembly of micrometric parts. Remove your watch for:

• Weightlifting with heavy loads (dumbbells, barbell)
• Racket sports (tennis, padel, squash)
• Golf
• DIY with vibrating tools (drill, hammer)
• Combat sports

Chemicals

Avoid prolonged contact with perfumes, sunscreens, essential oils, household products, concentrated chlorine, unrinsed seawater. These substances attack the seals and tarnish the steel and leather straps.

Reflex after sea or pool: rinse the watch under clear water, crown screwed in, then dry with a soft cloth.

Extreme temperatures

Avoid sudden variations: going from a hot shower to cold water, from a sauna to a pool, leaving the watch in a car in direct sunlight. Seals expand and contract, and humid air can be drawn into the case.

VI. Power reserve and wear

The NH35 movement has a power reserve of approximately 41 hours. If the watch is not worn for more than two days, it will stop.

To restart it, give the crown 25 to 30 turns in position 0, then set the time and date.

Daily wear of about 8 hours is sufficient to maintain automatic winding thanks to the rotor. If you alternate several watches, a watch winder can keep your pieces moving without manipulation.

VII. Expected accuracy

The NH35 movement is certified by its manufacturer to -20 / +40 seconds per day. This tolerance is normal for a mechanical movement in this range, compared to quartz watches, which are accurate to a few seconds per month but lack mechanical charm.

Actual accuracy depends on several factors:

• The position of the watch at night (dial up, crown down, etc.)
• Ambient temperature
• Winding level
• Daily activity

Tip: if your watch is running slightly fast, place it at night crown up. If it's running slow, place it dial down. These positions naturally compensate for a few seconds per day.

VIII. Routine maintenance

Case and steel bracelet

Dry microfiber cloth daily. For deeper cleaning, use a soft toothbrush soaked in lukewarm soapy water, then rinse and dry thoroughly—crown screwed in, of course.

Leather strap

Never get it wet. Avoid prolonged contact with perspiration, perfumes, and creams. A leather strap worn daily has a lifespan of about 1 to 2 years; it is normal for it to develop a patina and need replacement.

Sapphire crystal

Extremely scratch-resistant, but brittle if struck head-on against a hard corner. A microfiber cloth is sufficient for maintenance.

Complete overhaul

Every 4 to 5 years, a mechanical movement benefits from being serviced by a watchmaker: disassembly, cleaning, oiling, seal replacement. This operation significantly extends the watch's lifespan.

IX. What to do if…

The watch has stopped. Give the crown 25-30 turns in position 0, then set the time and date. If it stops again quickly, contact us.

The date does not jump precisely at midnight. A slight delay (a few minutes before or after) is normal for an NH35 and does not indicate a defect.

The crown is difficult to screw in. Never force it. Unscrew completely, reposition it straight in line, and screw gently. If resistance persists, contact us.

The watch suddenly gains or loses several minutes a day. Likely magnetization. A watchmaker can demagnetize the watch in a few minutes.

Condensation appears under the crystal. Immediately stop wearing the watch, with the crown screwed in, and contact our after-sales service. Water resistance is compromised.

A bracelet link has loosened. Do not lose it. Rescrew or replace the pin, respecting the direction of the arrows. If a screw is lost, we can send you one.

X. Never do this

❌ Set the date between 9 PM and 3 AM ❌ Unscrew the crown when the watch is wet or underwater ❌ Shower, use a sauna, or take a hot bath with the watch on ❌ Place the watch on a Bluetooth speaker or induction hob ❌ Keep the watch on your wrist during an MRI scan ❌ Force the crown at the end of winding or screwing ❌ Open the case back yourself (voids warranty and water resistance) ❌ Clean the case with abrasive products or solvents