21 Unworked or semi-worked glass-ceramics, namely, unworked or semi-worked crystallized-glass, not for building; unworked or semi-worked glass-ceramics, excluding construction/building materials, in flexible sheet and solid plate form used in further manufacture of electrochemical devices; unworked or semi-worked glass-ceramics, excluding construction/building materials, in flexible sheet and solid plate form used in further manufacture of battery components; unworked or semi-worked glass, not for building; frit, namely, ground glass used in glass manufacturing; frit, namely, ground glass used in glass-ceramic manufacturing; unprocessed or semi-processed powdered glass, not for building; unprocessed or semi-processed glass, not for building; processed glass-ceramics, namely, processed crystallized-glass, not for building; processed glass excluding construction/building materials.