National 20-121 Rip Proof Reinforced Paper 11 x 8-1/2", Pack of 100 Sheets. Heavyweight filler paper features a clear Rip-Proof film strip along the binding edge to prevent sheets from pulling through at ring binder holes. Ideal for price lists, parts lists, instruction manuals and other sheets that receive heavy usage. Though Rip-Proof Mylar film is remarkably strong, it has only 60 percent of the bulk of other reinforcing to allow more pages in ring binders. Each page of white bond paper has three 9/32" round holes already punched to save time while filing and organizing.