The white, write-on strip makes sample identification easier and more convenient. It's easy to write on this white strip using an ordinary ballpoint pen, pencil, or felt-tip marker. The paper-like finish virtually eliminates ink smearing, and provides a surface that will accept a variety of writing instruments. Giant size Whirl-Pak® bags to accommodate large size samples and eliminate reducing into smaller pieces. The closing tab has one round and one flat wire to ensure the bag is closed securely. Fold tab over tightly 4-5 times when closing, volume measurements are approximate.