Bought a box on EBay same stuff as far as I can tell, just all white. very strong paper. "letter trim perforations" is the type
Another choice is Stadeler 9# 25% cotton it gave me a 10thou bump in dia but is more expensive. Was going to check details on paper but can't find it. rapped on good and was fairly tough. I'll find the package and update this if I mispoke.