Material: The 5x7 envelopes are made of 110GSM paper they have moderate thickness and you can print the desired pattern on the envelope surface. Convenient to Use: When using them, just peel off the strip and seal the flap Smooth surface and is easy to write. Perfect Invitation Envelopes: The invitation envelopes are a great way to communicate with your friends and families and share your joy with them. Multipurpose: for expressing thanks or inviting others to the party, such as Birthday Parties, Weddings, Showers, graduation invitations, Thanksgiving, Christmas, etc. Weight: 1.52 pounds.