Clamshells are a convenient packaging solution. Why are they called Clamshells? Because they open, like a clam and then snap closed when you are ready to seal them. Clamshells are suitable for Melt & Pour Soap. Massage & Bath Melts and Soy Tarts and Melts. They are simple to use, quick and convenient. Pour, allow to set, close the lid, label and they are ready to go!