Avery 5389 Laser Postcards, Perforated, 4"x6", 100/BX, White Sold as 100/Box. Sturdy bright white cardstock and ultra-fine perforations let you separate cards cleanly and easily. Add color to the entire card on both sides. Easy to customize with free designs, QR codes and templates from Avery Design & Print. This product was made using wood sourced from a certified managed forest.