In the tv show The Big Bang Theory, Rajesh wears the Casio CA53W. This is the classic digital watch that has an alarm and chronograph, but most importantly a calculator. This watch was originally released in 1988 and it seems to be relatively (if not completely unchanged). This watch is so outdated it does not even have any kind of backlight which is available on the Casio F91w which came out 1 year later in 1989.

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