Non-metallic wall panels; plastic panels for use in building; cladding panels (non-metallic -) for walls; dividing wall panels (non-metallic -); indoor partitions, not of metal, other than furniture; structural support members (non-metallic -); fire-resistant panels, not of metal, for use in construction; concrete blocks; concrete block ballast; concrete blocks for supporting hoarding and partition walls; parts and fittings for all the aforesaid goods all made wholly or principally of non-met...