Glassine sleeves have been a favorite storage medium for photo professionals for packaging, handling and storage of negatives and photos. The translucent envelopes are made of archival, acid-free pH negative non-plasticized paper. Glassines can also be combined with archival sleeving for long-term storage. G-SV-20 contains a quantity of 1000 envelopes & G-SV-23 contains a quantity of 200 envelopes.