We provide the best preservation storage products available. Our products are used by the archivists of the top colleges & universities, government institutions, historical societies, museums, libraries, and commercial businesses. All of our products meet the highest standards of archival quality. Our materials have surpassed The International Organization for Standardization's ISO 14523 Standard in tests conducted at Rochester Institute of Technology. Our buffered boxes and folders are acid free with a minimum pH of 8.5, contain a 3% calcium carbonate buffer, and test negative for lignin and sulfur. All product measurements listed are inside dimensions. To obtain a free copy of our 128 page catalog, please call our toll free customer service phone line: 800/634-0491; or our toll free fax number: 800/947-8814.