- No. 9 envelopes: Sometimes called “response” envelopes because their smaller size makes them fit perfectly inside a #10. They measure 8.875” by 3.875” and can be solid, windowed or double-windowed.
No. 9 envelopes, or response envelopes, are slightly smaller than the standard letter-size business envelope. They measure 8.875” x 3.875”, small enough to fit snugly inside a standard envelope while still the right size for most documents and letters.
9 x 12 Catalog
- Catalog envelopes: 9” by 12” sturdy envelopes with the flap on the narrow side, these are great for mailing documents that can’t be folded, thicker documents, and other types of lengthy correspondence. These are also available in windowed and non-windowed styles.