Gives the requirements for three types of non-heat-shrinkable sleeving, extruded from PTFE. Sleeving of this type is normally available with internal diameters up to 8,53 mm and in a range of wall thicknesses between 0,15 mm and 0,51 mm. This specification covers three levels of wall thickness: "thin wall", "standard wall" and "thick wall" related to nominal internal diameter and with corresponding differences in requirements for breakdown voltage. Experience of product performance indicates that PTFE sleeving may be suitable for inclusion in systems for operation at temperatures up to 250 °C.