Archival Postcard Box Spacer. 4-3/8" tall x 21-14" long. E-flute Corrugated. Fold on scores as box fills. Use in boxes x799-0405, x45bbbg, x45bbk.**NEW**
Postcard Archival Box Spacer
21-1/4 x 4-3/8" Blue E-flute corrugated cardboard. Acid-free, lignin-free with a 3% calcium carbonate buffer. Fold spacer on scores as box fills with postcards to keep postcards upright. Fits in postcard storage boxes x799-0405, x45bbbg, x45bbk.