What is the slide rule bezel used for?

This is based on a circular slide rule known as E6B, frequently used in aviation. It is for this reason that you may also see this referred to as an E6B bezel. Users interested in learning to use an E6B may find the following page from Wikipedia to be helpful as a starting point:

http://en.wikipedia.org/wiki/E6B

Keep in mind that this is a feature that is geared toward aviation applications, and many people involved in the aviation industry should already understand how to use it. Our technical support team is unable to provide assistance in teaching users to work calculations with a slide rule bezel.

Some Casio models that feature a slide rule bezel include MTP4500D-1AV, MTP4700D-2AV, and EF527D-1AV.