LUXPaper A4 Foil Lined Invitation Envelopes | Peel and Press | 4 1/4" x 6 1/4" | Natural w/Black LUX Lining | 70lb. Text | 50 Qty. Size :A4 Invitation Envelopes (4 1/4 x 6 1/4) with Peel & Seal. When using A4 Invitation Envelopes with Peel & Seal, it's important to ensure that the invitations are neatly and securely placed inside to maintain a professional appearance.