White through-out Board, Ply Board sometimes called Posterboard, RailroadBoard, WhiteBacking, WhiteBlanks, thickness ranges from 4ply to 14ply, please read the descriptions below to find the right thickness for your uses.

Thickness Descriptions:

4ply - Most call this Poster Board, we call it 4ply. If you are in need of a board stiffer than cardstock, this is it. It is not printable though. This 4ply is foldable by hand, best results are with a bonefolder. Can cut with scissors, best results with a straight edge and a knife. 4ply, 22x28"
6ply - Similar to the stocks used in small light-weight white giftboxes, this is used mainly in mounting and making prototypes to packaging. It is way thinner than any mat/illustration board. This 6ply is foldable by hand, best results are with a bonefolder. Can cut with Heavy Duty scissors, best results with a straight edge and a knife. 6ply, 22x28"
10ply - This is almost as half the thickness of most mat/illustration boards. This 10ply is very stiff and best cuts are done with a straight edge and a knife. 10ply, 22x28"
14ply - Thick as most mat/illustration board, it's main uses are mounting and stiffening. Cannot cut with any scissors (at least we do not recommend it). Still difficult to cut with a knife (it might need several cuts to actually cut apart). It is strong and stiff-reliable to stay its shape. 14ply, 22x28", 28x44" or 30x40"

Features:

Color: White
Size: 22x30", 28x44", 30x40"
Thickness: 4ply, 6ply, 8ply, 10ply, 14ply
Weight:

PANTONE FORMULA GUIDE

Ply/White Blank Boards (Multiple Sizes & Thicknesses)