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- 1). Turn your watch over so that it is face down.
- 2). Look at the back of the timepiece. There are two numbers. The first is your watch's model number (sometimes called reference number). The second is your watch's serial number. While each watch style has the same model number, no two watches have the same serial number.
- 3). Determine your model number. The number begins with two or three letters followed by five digits. It will look like "XX00000" or "XXX00000."
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