Go to
http://www.equilter.com and search for MSFCRTGR which is the product code for white flannel with printed grid. I have used this on a couple of design walls. I clean the threads off of it periodically with a lint roller that I keep to clean my olfa mat.
"This clean design on flannel from Maywood Studios features a grid, composed by thin jade line and a white ground. Simple, attractive, and very functional. 56" wide, grid squares are about 2", 100% cotton Creative Grid. Can be used for laying out quilt designs - for wall design boards or tables. Works well for constructing ironing board covers."