semi-worked rubber products, namely, molded parts of rubber for use in manufacturing shoes; semi-processed plastic materials and resins; semi-processed plastic materials; semiprocessed synthetic resins; semi-processed synthetic resins in the form of sheets for use in manufacturing operations; extruded plastics in sheet form for use in manufacturing operations; semi-processed synthetic resins in the form of blocks for use in manufacturing operations; extruded plastics in the nature of blocks f...