Copolymer of vinylidene chloride with acrylonitrile, in the form of expansible beads of a diameter of > 4 micrometres but < 20 micrometres
Vinylidene chloride polymers, in primary forms (excl. copolymer of vinylidene chloride with acrylonitrile, in the form of expansible beads of a diameter of > 4 but < 20 micrometres)