We are pleased to offer for sale these BCW Polypropylene Sleeves for Business Envelope #10, pack of 100. These Business Envelope Sleeves are made of completely transparent 2 mil polypropylene. This material is acid-free and archival quality, making these #10 Envelope Storage Sleeves ideal for long term storage. The dimensions of theseEnvelope Storage Sleeves are 4 1/4" x 9 5/8". Envelope will hold one #10 Business Envelope.