3913 Natural Polymers, E.g. Alginic Acid, and Modified Natural Polymers, E.g. Hardened Proteins, Chemical Derivatives of Natural Rubber, N.e.s., in Primary Forms
3913 Natural Polymers, E.g. Alginic Acid, and Modified Natural Polymers, E.g. Hardened Proteins, Chemical Derivatives of Natural Rubber, N.e.s., in Primary Forms