Whether you're at home or at the office, #9 envelopes can handle all of your mailings. These fundraising envelopes are perfect for mailing your donations. Measuring in at 3.875 x 8.875, these standard size envelopes are complete with a secure gummy closure and a v-flap. These envelopes are very affordable, but certainly not cheap! Made with 24lb paper, rest assured that your mailings will be safe and sound. Also known as return envelopes, they fit right inside our #10 envelopes! They can also be known as business reply envelopes because of that reason!