Lig-Free I papers are lignin and sulfur-free, contain a minimum 3% alkaline buffering, pass PAT, and have a pH of 8.5. They are highly calendared to give them a smooth texture, and come in a pleasing tan color. Our folder paper offers a vital combination of correct chemical composition and physical endurance. All too often, the importance of strength and durability is overshadowed by concerns about the chemical content of a given paper. Our folder stock goes well over 1000 double folds in the weakest direction at 1 kg. load, as per the MIT Folding Endurance Test. This paper is sold by the sheet. Usual grain direction is 30 for 30 x 40 sheets, 36 for the 36 x 48, 60 in the 40 x 60 sheets, and 72 for the 48 x 72 size.