A sliver consists of staple fibres of short lengths, usually less than 380 mm in length. The staple fibres are loosely arranged in parallel fashion into a rope-like strand with little or no twist (less than 5 turns per metre). Slivers are generally used to produce staple fibre yarn, but may also be used in the manufacture of wire and cable. Yarn of this subheading is twisted, and of either continuous filament or staple fibre. Yarns are usually supplied either on plastic bobbins or on metallic warp beams. They can be also texturised or voluminised. In this process the glass yarns are overfed in a nozzle in which an airstream creates turbulence that causes the formation of loops and imparts a slight (texturising) or high (voluminising) bulk. These types of yarns are usually supplied on cardboard tubes and are used in various applications such as: - wall covering woven fabrics to avoid a flat aspect, - woven fabrics for roofing, - thermal insulation products.