Clam Shells not only protect your discs from breaking, they protect the cases themselves from breaking apart too. Unlike jewel cases that are made of brittle plastics, clam shells are made of translucent soft plastics. If you need to send your discs by mail (either by US Postal, FedEx, or UPS), don’t even think about using jewel cases unless they are wrapped with heavy duty protection. They will be broken for sure. But using clam shells will guarantee your discs to have a safe journey.