To try our system, simply measure 4 books or items and email the dimensions either in the body of the email or by attaching a spreadsheet or word doc. A suggested format is listed below. We will ship the boxes within a few days of receiving the order, marked in the order measured. For this trial offer, some size restrictions apply. We will contact you with any size restriction information, if applicable. Email cmiboxes@archivalboxes.com for details or questions.