Easily customize your own promotional advertising, product instructions, thank you cards, and other postcards for mailing using Avery Design & Print Online and available templates Each sheet of printable cardstock features proprietary Sure Feed technology that delivers a more reliable feed through your laser printer to reduce misalignments and jams Enjoy a clean, professional finish from the micro-perforated design that allows for easy separation and a smooth border around each postcard Print beautiful, double-sided designs on postcard paper made from heavyweight 80 lb / 216 gsm uncoated white cardstock, optimized for laser printers, ensuring crisp, smudge-free printing Item includes 50 printable 8.5" x 11" sheets with a total of 100 blank 4" x 6" rectangle cards (two cards per sheet) that meet U.S. postal regulations for postcards; just address, stamp, and mail-no envelope required!