6 Square Invitation Envelope - 24# White (6 x 6) - Announcement Envelope Series (Box of 250) A Quantity of 250 - 6 SQ Invitation Envelope - 28# White 24# White Wove Paper - Regular Gummed Flap. The outside dimension of this envelope is 6 x 6. This envelope is meant for invitations or inserts that are 5 1/2 Square or smaller. Perfect for Greeting cards, Weddings or any announcement. This envelope may be sourced from any one of a number of top brands. Ships via UPS Ground