In the Print-on-Demand process used by Lightning Source, books are printed and manufactured in a one-off model using both automated and manual processes. Each book is manufactured in its entirety, every time an order is placed. Due to slight changes in production from day to day, variations in printing and manufacturing are a common occurrence. Likewise, submitted files that do not meet our recommended technical specifications can produce a printed product that differs from the digital file and/or eproof. We make provisions for, and indicate in our company documentation, that there may be up to a 1/16” shift or +/-0.1 color density variation on any book manufactured by Lightning Source. Orders outsourced to other printers we have partnered with will also meet Lightning Source print requirements and acceptable variations.