This is Chipboard Binding Covers.
They come in sizes ranging from 5.5" x 8.5" up to 12" x 18".
You can choose to add a custom window to your covers or add rounded corners to your oversized cover sheets.
The most common use of Chipboard is as a back cover, supporting your project so it doesn't wrinkle and making it easier to write on the pages.
Even select from 8 punch patterns to receive your pages prepunched.
Look for the variations in thickness, from 18pt to 48pt.
Our chipboard is made completely of 100% recycled material.