Construction: Fine strands of bare copper wire with PVC inner sheath. Overall screen made of tinned steel wire braid with transparent PVC outer sheath. Standards: Generally to BS6500, VDE0250 Conductor: Class 5 flexible annealed copper conductors to BS EN 60228:2005 (previously BS6360), VDE0295, IEC 60228 Standard Colours: Cores - Black with White numbers. (3 cores and above to include Green/Yellow earth conductor). Voltage Rating: 300/500 Volts Temperature Rating: Fixed: -35°C to +70°C, Flexing: -15°C to +70°C.