The following link provides an overlay that can be printed and inserted into the device.
Core Vocabulary
The Universal Core vocabulary is a set of 36 highly useful single words that can be used alone or in combination to communicate for a range of purposes on countless topics with a wide variety of communication partners.
Several formats are available to support student access through direct pointing or touch, eye gaze selection, and partner-assisted scanning. Additionally, high contrast versions are available to address the needs of some students with visual impairments and 3D symbols are available for students who are blind.
All formats are available for free download and printing from: http://www.project-core.com/communication-systems/.