A 3-side seal pouch is formed by sealing three edges of the pouch, leaving one side open for filling. This pouch packaging format is produced by folding a single sheet of film in half or aligning two identical film layers, then sealing the left, right, and bottom edges. The result is a flat, compact pouch with a clean appearance and stable sealing structure. Three-side seal pouches are widely used for products that require simple packaging formats, efficient material use, and consistent presentation.