No, the symmetrical and unsymmetrical versions have different chemical structures and different deposition properties. Pure parylene C is symmetrical dichloro paracyclophane. The symmetrical version has one chlorine attached to each of the two monomers. This produces the most uniform and predictable deposition behavior and film. The unsymmetrical version has one monomer with two chlorine atoms and one monomer with no chlorine atoms, so it is a combination of parylene D and Parylene N. The unsymmetrical version will have less predictable deposition behavior and mixed film properties, this can be a problem for highly regulated technologies like medical devices.