This traditional interleaving material is translucent, acid-free, and unbuffered. Use glassine (25#, 40 gsm) for a variety of conservation applications. The surface is very smooth and has a pH of 7.0. Its light weight makes it easy to fold yet it maintains its shape well. Often used for interleaving watercolor and charcoal drawings but is not recommended for long-term photographic storage. Price per package of 12 sheets.