INSTRUCTION MANUAL

Thank you for your purchase of this Citizen watch.

English
Before using the watch, read this instruction manual carefully to ensure
correct use.
After reading the manual, store it in a safe place for future reference.
Be sure to visit the Citizen website at https://www.citizenwatch-global.com/ .
Here you will find a variety of information such as electronic setting guides,
answers to frequently asked questions, Eco-Drive recharging information and
more.

To check the movement number Engraving position example

A case number—4 alphanumeric characters and 6 or
more alphanumeric characters—is engraved on the
case back. (Figure on the right)
The first 4 characters of the case number represent
the movement number of the watch. In the example The engraving position may
on the right, “ ” is the movement number. differ depending on watch
model.
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 Safety precautions — IMPORTANT
This manual contains instructions that should be strictly followed at all times
not only for optimal use, but to prevent any injuries to yourself, other persons
or property. We encourage you to read the entire booklet (especially 20 - 29) and
understand the meaning of the following symbols:
■ Safety advisories are categorized and depicted in this manual as follows:

DANGER Highly likely to cause death or serious injury

WARNING Can cause serious injury or death

CAUTION Can or will cause minor or moderate injury or damage

2
 Safety precautions

English
■ Important instructions are categorized and depicted in this manual as follows:
(Following symbols are examples of Pictograms.)

Warning (caution) symbol followed by prohibited matters.

Warning (caution) symbol followed by instructions that should be

followed or precautions that should be observed.

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 Safety precautions
Precautions to be taken when diving
PROHIBITED Do not use this watch while diving when...
• Do not use your watch while diving when the watch stops or exhibits any
abnormal operation.

CAUTION Diving with the watch

• Persons using the diver’s watch are strongly recommended to receive proper
instruction and training pertaining to diving and observe those rules at all times.
• Please use this watch properly only after you fully understand the operating
procedures and cautions.
Using this watch other than as indicated in this instruction manual may result in
failure of the watch to function properly.
• Check the water-resistant indications on the watch face or the case back. Never
dive beyond the indicated depth.

4
 Safety precautions

English
CAUTION Before diving
• Check items below before diving
- Make sure that the mainspring is fully wounded
- Make sure that the watch is running correctly (check the movements of the
time/calendar/second hand)
- Make sure that the crown is fully pushed in and its screw is tighten firmly
- Make sure that the band is firmly anchored to the watch body.
- Make sure that there are no cracks or other damage to the watch band or the
glass face.
- Make sure that the register ring rotates properly.

CAUTION During diving

• Do not operate the crown in the water. Operating any of them in water may cause
trouble including deterioration of water resistance.
• Be careful not to hit the watch against hard objects such as equipment or rocks.

CAUTION After diving

• Check to see if the crown is pushed in and locked before removing the sea water,
dirt, and sand attached to the watch with fresh water. Then, wipe the fresh water.
5
 CONTENTS
Characteristics of Mechanical watches. . . . . . . . . . . . . . . . . . . . . . . 7
Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Before using this watch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Component identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Mainspring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Adjusting the time and calendar. . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Using the rotating bezel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Water resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Precautionary items and usage limitations. . . . . . . . . . . . . . . . . . 22
Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

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 Characteristics of Mechanical watches

English
About time accuracy of mechanical watches
The time accuracy described on this instruction manual is the static accuracy
at normal temperature. The accuracy of mechanical watches may get out of the
described range depending on the following three usage conditions or other reasons.
• Winding amount of the mainspring
• Attitude
• Usage environment (temperature, magnetism, impact, etc.)

Winding amount of the mainspring Attitude

Mechanical watches keep accuracy Accuracy of mechanical watches varies
most stably when the mainspring is affected by gravity. The accuracy varies
sufficiently wound. as the result that may take various
attitude while worn and gravitate to a
different direction every moment.

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 Characteristics of Mechanical watches
Usage environment (temperature, magnetism, impact, etc.)
• ‌Metal parts are used for the part for keeping accuracy in mechanical watch. The
accuracy varies affected by their thermal expansion and contraction.
• ‌Metal parts are used in mechanical watches. Magnetism affects them and
accuracy of the watches in consequence. Do not bring them close to things which
have or generate strong magnetism.
• Strong shocks may also affect the accuracy.

Maintenance
Mechanical watches may become inaccurate due to insufficient lubrication or worn
parts. Have the watch disassembled and cleaned (overhaul) every 2-3 years (charge
basis). It may be difficult to restore the watch from degradation after long-term use
to its initial performance even after repairs.

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 Features

English
■ Water-resistant to 200m
• ‌This watch is a SCUBA diver’s watch (water-resistant to 200m). You can use it
for SCUBA diving with air tanks, but must not be used in a helium-enriched
atmosphere (e.g. saturation diving).
■ Automatic winding movement
• ‌A automatic winding movement is employed in which the watch mainspring
is wound automatically by movement of the hand when worn, and the force of
the mainspring is then used to drive the movement (watch).
[Automatic winding]
When worn on the wrist, the normal movement of the arm will wind the mainspring.
[Manual winding]
Rotate the crown clockwise while it is in position to wind the mainspring.

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 Before using this watch
Band adjustment
We recommend seeking the assistance of an experienced watch technician
for sizing of your watch. If adjustment is not done correctly, the bracelet may
unexpectedly become detached leading to loss of your watch or injury (excluding
products containing the band adjustment tool).
Consult an authorized service center.

Protective stickers
Be sure to remove any protective stickers that may be on your watch (case back,
band, clasp, etc.). Otherwise, perspiration or moisture may enter the gaps between
the protective stickers and the parts, which may result in a skin rash and/or
corrosion of the metal parts.

10
 Before using this watch

English
How to use a specially designed crown
Unlock the crown prior to operate your watch.
Unlock Lock
Push the crown in to
the case. With gentle
Rotate the crown
pressure towards the
Screw down counterclockwise
case, rotate the crown
crown until it releases from
clockwise to secure it
the case.
to the case. Be sure to
tighten firmly.

11
 Before using this watch
Cautions for this automatic winding watch
• ‌The mainspring of this watch is automatically wound when it is worn on your
wrist. But when not worn, the mainspring will run out in about 2 days and the
watch will stop.
• ‌Wind the mainspring sufficiently before adjusting the time (the hour and minute
hands).

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 Component identification

English
Rotating bezel Minute hand

Hour hand
Crown

Date

Second hand

• The illustrations in this instruction manual may differ from the actual appearance
of your watch.
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 Mainspring
This watch runs using the power of the mainspring.
• Once the mainspring is wound fully, it will run for about 42 hours.
• ‌Sufficient winding ensures stable and accurate movement.
Winding the mainspring
This watch is an automatic mechanical watch. (You can also wind the mainspring
manually.) The mainspring is wound by swinging your arm. It is recommended to
wear the watch for more than 8 hours a day. If you do not move your arms much
in your daily life, for example you spend a lot of time sat at a desk, the mainspring
may not be wound sufficiently. In such cases, wind the mainspring manually.

CAUTION
This watch is equipped with the screw down crown to get higher water resistance.
Rotate the crown counterclockwise to unlock it before its operation. After the
operation, push the crown in to the normal position, then rotate it clockwise
while pressing it toward the case to tighten the screw firmly.

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 Mainspring

English
Winding the mainspring manually
Push the crown in position . Hold the crown with your thumb and index finger
and rotate it clockwise slowly.

Crown

• ‌When the watch stops, turning the crown about 40 times will wind the
mainspring fully.
• ‌When the mainspring is wound fully, turning the crown further does not damage
the mainspring.

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 Adjusting the time and calendar
1 Pull the crown out to position .
2 Rotate the crown clockwise to make the date indicating a
day before the date you want to set.
3 Pull the crown out to position .
4 Rotate the crown counterclockwise to set the date.
•T
 he time become AM when the date indication is changed.
5 Rotate the crown to set the time.
•P
 ut the hour hand beyond 12 o’clock once when you want to
set time of PM.
6 Push the crown in to position to finish the procedure.

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 Adjusting the time and calendar

English
• ‌Do not adjust the date indication when the watch shows 8:30 PM - 2:00 AM.
Otherwise the date indication may change improperly.
When you want to adjust the calendar, move the hands out of the period above
temporarily, then adjust it.
• ‌The date indicator on the watch is based on a 31-day calendar. Adjust the date
indication on the first days of March, May, July, October and December.

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 Using the rotating bezel
You can find the elapsed time of diving or remaining time to a target time.
• ‌To prevent accidents, the rotating bezel moves counterclockwise only.

Finding the elapsed time

Rotation direction
1 Rotate the rotating bezel to set the ○ mark
○Mark to the current position of the minute hand.
• Suppose the position of the ○ mark as
0 minute.
2 Read the position of the scale on the
rotating bezel which the minute hand
Elapsed time points to find the elapsed time.
• 10 minutes has passed in the illustration.

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 Using the rotating bezel

English
Finding the remaining time
Rotation direction
Current position of
the minute hand 1 Rotate the rotating bezel to set the ○ mark
to the target time.
• The target time is set to 20 minutes after the
current time in the illustration.
2 Read the time between the current position
of the minute hand and that of the ○ mark
to find the remaining time.

Remaining time from the position

of the minute hand
to that of the ○ mark (target time)

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 Water resistance
WARNING Water resistance
• ‌Diver’s water-resistant watches can be used only for SCUBA diving using an air
tank and not for saturation diving using a helium gas tank.
• Complies with ISO6425:1996 or ISO6425:2018.
*Standards that the watch complies with differ with watch models.

Indication

Name Specification

Dial or Case back

Water-resistant watch DIVER'S 200m

200m water resistant
for SCUBA diving DIVER'S WATCH 200m

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 Water resistance

English
• ‌The packing used for this watch is a consumable part and will deteriorate over
long-term use. Deterioration may lead to water penetration, causing the watch
to malfunction or stop. Consult an authorized service center for inspection (for
a charge) every 2 or 3 years, and replace the packing, glass or other parts as
necessary.

Water-related use

Minor Operate the

exposure to Swimming SCUBA diving Saturation crown or
water (washing and general Skin diving, using an air diving using button when
face, rain, etc.) washing work marine sports tank helium gas the watch is wet

OK OK OK OK NO NO

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 Precautionary items and usage limitations
CAUTION To Avoid Injury
• Be particularly careful when wearing your watch while holding a small child, to avoid injury.
• Be particularly careful when engaged in strenuous exercise or work, to avoid injury to yourself
and others.
• Do NOT wear your watch while in a sauna or other location where your watch may become
excessively hot, since there is the risk of burns.
• Be careful when putting on and taking off your watch, since there is a risk of damaging your
fingernails, depending on the manner in which the band is fastened.
• Take off your watch before going to bed.

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 Precautionary items and usage limitations

English
CAUTION Precautions
• Always use the watch with the crown pushed in (normal position). If the crown is of the screw
lock-type, make sure it is securely locked.
• Do NOT operate the crown or any push buttons when the watch is wet. Water may enter the
watch causing damage to vital components.
• If water enters the watch or the watch fogs up and does not clear up even after a long time,
consult your dealer or an authorized service center for inspection and/or repair.
• Even if your watch has a high level of water resistance, please be careful of the following.
- If your watch is immersed in sea water, rinse thoroughly with fresh water and wipe with a
dry cloth.
- Do not pour water from a tap directly onto your watch.
- Take off your watch before taking a bath.
• If seawater enters the watch, place the watch in a box or plastic bag and immediately take it in
for repair.
Otherwise, pressure inside the watch will increase, and parts (crystal, crown, push button,
etc.) may come off.

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 Precautionary items and usage limitations

CAUTION When Wearing Your Watch

<Band>
• Leather bands and rubber (urethane) bands will deteriorate over time due to perspiration or
dirt.
In addition, they are made of natural material and will be worn, deformed and discolored over
time. It is recommended to replace the band periodically.
• The durability of a leather band may be affected when wet (fading, peeling of adhesive), owing
to the properties of the material. Moreover, wet leather may cause a rash.
• Do not stain a leather band with substances containing volatile materials, bleach, alcohol
(including cosmetics). Discoloration and premature aging may be occurred. Ultraviolet light
such as direct sunlight may cause discoloration or deformation.
• It is recommended to take off the watch if it gets wet, even if the watch itself is water-resistant.
• Do not wear the band too tightly. Try to leave enough space between the band and your skin
to allow adequate ventilation.
• The rubber (urethane) band may be stained by dyes or soil present in or on clothing or other
accessories. Since these stains may not be removable, caution is required when wearing
your watch with items that tend to easily transfer color (articles of clothing, purses, etc.). In
addition, the band may be deteriorated by solvents or moisture in the air. Replace with a new
one when it has lost elasticity or become cracked.

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 Precautionary items and usage limitations

English
• Please request adjustment or repair of the band in the following cases:
- You notice an abnormality with the band due to corrosion.
- The pin of the band is protruding.
• We recommend seeking the assistance of an experienced watch technician for sizing of your
watch. If adjustment is not done correctly, the bracelet may unexpectedly become detached
leading to loss of your watch or injury (excluding products containing the band adjustment
tool).
Consult an authorized service center.
<Temperature>
• The watch may stop or the function of the watch may be impaired in extremely high or low
temperature.
<Magnetism>
• Parts of the movement may be magnetized in a strong magnetic field and it may adversely
affect accuracy of the watch. Do not allow the watch to come into close proximity to
magnetic health devices (magnetic necklaces, magnetic elastic bands, etc.) or the magnets
used in the latches of refrigerator doors, clasps used in handbags, the speaker of a cell phone,
electromagnetic cooking devices and so on.

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 Precautionary items and usage limitations
<Strong Shock>
• Avoid dropping the watch or subjecting it to other strong impact. It may cause malfunctions
and/or performance deterioration as well as damage to the case and bracelet.
<Chemicals, Corrosive Gasses and Mercury>
• If paint thinner, benzene or other solvents or products containing these solvents (including
gasoline, nail-polish remover, cresol, bathroom cleaners and adhesives, water repellent, etc.)
are allowed to come into contact with the watch, they may discolor, dissolve or crack the
materials. Be careful when handling these chemicals. Contact with mercury such as that used
in thermometers may also cause discoloration of the band and case.
<Protective Stickers>
• Be sure to remove any protective stickers that may be on your watch (case back, band, clasp,
etc.). Otherwise, perspiration or moisture may enter the gaps between the protective stickers
and the parts, which may result in a skin rash and/or corrosion of the metal parts.

26
 Precautionary items and usage limitations

English
CAUTION Always Keep Your Watch Clean
• Rotate the crown while it is pressed in fully and press the buttons periodically so they do not
become stuck due to accumulations of foreign matter.
• The case and band of the watch come into direct contact with the skin. Corrosion of the metal
or accumulated foreign matter may result in black residue coming from the bracelet when
exposed to moisture or perspiration unnoticed soiling such as that caused by perspiration. Be
sure to keep your watch clean at all times.
• Be sure to periodically clean the bracelet and case of your watch to remove accumulated
dirt and foreign matter. In rare circumstances, accumulated dirt, foreign matter may cause
irritation with the skin. If you notice this, discontinue wearing the watch and consult your
physician.
• Be sure to periodically clean foreign matter and accumulated materials from the metal band,
synthetic rubber strap (polyurethane) and/or metal case using a soft brush and mild soap. Be
careful not to allow moisture on the case if your watch is not water resistant.
• Leather bands may become discolored by perspiration or dirt. Always keep your leather band
clean by wiping with a dry cloth.

27
 Precautionary items and usage limitations
Caring for Your Watch
• Wipe any dirt or moisture such as perspiration from the case and crystal with a soft cloth.
• For a metallic, plastic or rubber (urethane) watchband, wash any dirt off with water. Remove
the small amounts of dirt trapped between the crevices of the metallic band with a soft brush.
• For a leather band, wipe off dirt using a dry cloth.
• If you will not be using your watch for an extended period of time, carefully wipe off any
perspiration, dirt or moisture and store in a proper location, avoiding locations subject to
excessively high or low temperatures and high humidity.

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 Precautionary items and usage limitations

English
When Luminous Paint is used for your watch
The paint on the dial and hands helps you with reading the time in a dark place. The
luminous paint stores light (daylight or artificial light) and glows in a dark place.
It is free from any radioactive substance or any other material harmful to a human body or
environment.
• The light emission gradually becomes weaker as time passes.
• The duration of the light (“glow”) will vary depending on the brightness, types of and
distance from a light source, exposure time, and the amount of the paint.
• The paint may not glow and/or may dissipate quickly if exposure to light was not sufficient.

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 Specifications
Model 9051

Number of jewels 24

Type Automatic mechanical watch

Accuracy in use –10 seconds to +20 seconds

• Time: hours, minutes, seconds

Display functions
• Calendar: date

Duration More than approx. 42 hours

Beats 28,800 times per hour (8 beats)

Manual No. B8209

Specifications and contents of this booklet are subject to change without prior notice.

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Model No.NB6＊
Cal.9051
CTZ-B8209