Citizen 2502 Instruction Manual page 13

case back and dial. and refer to the following table for the use of your watch.
type crowns, screw should be tightened completely.
Using it during
kitchen work,
Using it while skin
swimming, washing a
diving.
car, boating or water
skiing.
OK
OK
Water-related use
Using it while scuba
diving.
OK
OK
Using it in a saturated
diving (helium gas)
environment such as
used for professional
diving.
OK NO
OK OK
pulling out the crown
when the watch is
wet.
NO
NO
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