17 Rubber raw or semi-worked, gutta-percha, gum, asbestos, mica and goods made from these materials, namely, parts of machines, apparatuses, instruments and equipment for the industry, namely, gear wheels, housings, axles, containers, frames, shells, cages, boxes, connectors, cam rollers, runners, collars; plastics in extruded. casted or moulded form for general industrial use, lactam-based plastics in extruded, casted or moulded form for general industrial use; synthetic plastic as semi-finished products in form of foils, plates, rods, profiles, hoses, tubes, blocks, slabs and their cuttings; insulating materials made of plastics used for packing and sealing; flexible pipes, not of metal; semi-finished mould casting parts of plastic for use in a variety of industries