20mm A halogen free nylon conduit system self-extinguishing material properties. It is highly resistant to ageing, weathering and ultra violet light. 16.6mm id 21.2mm od supplied in 50M coils. Colour black. Construction Nylon reinforced spiral with a smooth bore. Temperature rating -40 to +120 C. Protection rating IP55 with sealing ring IP67. Flammability Self extingushing with 10 second flame resistance. Oxygen index 28%. Resistance definition Class 1 light 150 newtons. Mechanical tensile strength Class 2 light 250 newtons.. 50m in length.