Size S = Pack of 500, A4 Size (4.25 x 6.25 inches) Size M = Pack of 500, A6 Size (4.75 x 6.5 inches) Size L = Pack of 500, A7 Size (5.25 x 7.25 inches). Each package contains 500 envelopes-an ample quantity sufficient to meet the needs of weddings, graduation ceremonies, birthday parties, holiday celebrations, various gatherings, and business events. Effortless Self-Sealing: Features a convenient self-adhesive strip simply peel off the protective liner to seal-no licking or glue required. The strong adhesive ensures a secure, reliable seal every time.Printer Compatible: Suitable for use with both laser and inkjet printers, allowing for easy, direct printing of addresses without issues such as ink smudging or paper jams. Neat Storage: Includes a sturdy, durable storage box designed specifically for organizing and storing the envelopes neatly. Weight: 5.3 lbs.