Pro 7900 and 9900 Field Repair Guide 10/6/10
Print Head Pictures Printer Component, Software Item, LCD Display, Printer Button Page 379.
7900 and 9900 Head Rank Sticker
A Head Rank Sticker with black letters on a white background is
intended for a 7900 or 9900 only.
A Head Rank Sticker with white letters on a black background
is intended for a 7700, 9700, 7900, or 9900.