Emphasis added to the last sentence. Participation makes things better.
“QUALITY CONTROL N° 6484
Every notebook is handmade and it has been carefully checked for quality. If, despite our best efforts, we have overlooked a defect of any kind, please let us know. Send an e-mail to: email@example.com, and include a digital photo that shows the problem you found, the quality control number (that identifies the notebook in your hands) shown here, along with the model name and your mailing address. We will send you a new notebook.
Together, we can prevent mistakes in the future. Thank you.“