What did the customer mail back to Rochester, New York?

Answer

The entire camera

A defining feature of the original Kodak service model, based on the slogan 'You press the button, we do the rest,' required the user to return the complete apparatus when finished. After capturing the 100 available exposures, the customer shipped the entire box camera back to the Eastman Kodak factory in Rochester, New York. Upon receipt, Eastman's staff would develop the film, print the images, reload the camera with a new 100-exposure roll, and return the complete, ready-to-use package to the customer. This mandatory return of the hardware ensured quality control over the subsequent steps and locked the customer into the ongoing service cycle.

What did the customer mail back to Rochester, New York?
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