The opening on the ziplock poybag is always on the width dimension. Ziplock bags are measured by inside usable dimensions (without the zipper or lip included in the size).
All ziplock poly bag sizes meet FDA and USDA specifications for food. Your product's contents are always visible through these clear low density polyethylene bags.
The zipper type seal makes these bags reclosable and perfect for items that need to be kept fresh or repackaged.