PTFE Insulated wires and cables are divided into six sub-groups according to the construction and applications.  The common features are:

Conductors

• Silver Plated Copper (SPC) for use up to 200°C (minimum 1 micron silver coating as per ASTM-B-298)
• Nickel Plated Copper (NPC) up to 260°C (minimum 1.25 micron nickel coating as per ASTM-B-355)
• Silver Plated High Strength Copper Alloy (SPHSCA) for mechanical strength in fine cross-sections and for superior flex-life (somewhat lower conductivity than copper) generally as per ASTM-B-624
• Pure Nickel for use up beyond 260°C; very high resistance to corrosion; DC resistance about 6 times that of copper at 20°C
• Resistance alloys for Thermo-Couple applications
• Silver Plated Copper Clad Steel (SPCCS) commonly used for RF coaxial cables) as per ASTM-B-501
• Spiral multi-strands on glass-fibre cord for high linear resistance -- generally for heating applications
• Plain copper or Tinned copper can not be used due to high-temperature processing and applications; tin melts and flows into the interstices of stranding to make the conductor inflexible; copper tends to oxidize and become brittle

Sizes/Strandings

• Single strands from 0.05 to 1.02 mm (0.002" to 0.040"), or more
• 7, 19, 37, 61 true concentric strands, or 133 strands rope-lay (19 x 7)
• Even AWG sizes from AWG 34 to AWG 6 (AWG 4 under development)
• Odd AWG sizes and other type of strandings/bunchings also available
• Integrated conductor facility ensures tighter control on resistance, diameter, finish etc.
• For further details, please refer to size table

Insulation/Dielectricis always PTFE (Poly Tetra Fluoro Ethylene C₂F₄) which is the safest, cleanest, and most stable fluoro-carbon.  Click here for Properties of PTFE.  Multi-lap tape-wrapped sintered for 

• 250 V AC RMS (so called Type ET with nominal 0.17 mm radial wall thickness in 3 layers)
• 600 V AC RMS (Type E, 0.25 mm - 0.010" - nominal radial wall)
• 1000 V AC RMS (Type EE, 0.38 mm - 0.015" - nominal radial wall)
• For further details, please refer to size table

Compounded PTFE for High Voltage Cables; Sandwiched Polyimide (Kapton ®) Film for protection of PTFE from radiation. 

Colours are 10 standard electronic as per MIL-STD-104, plus shades and stripes; details here

Metal Shields/Sheaths

• Round wire silver plated copper (SPC) or nickel plated copper (NPC)
• SPC or Plain Copper Flat Foil 
• SS wires

Shielding methods

• Braided
• Served for lower overall diameter, especially for triaxial constructions
• Aluminised Polyester Film with drain wire (not compatible with PTFE jackets)
• Combination of Flat foil with round wire braid or Aluminised Polyester with round wire braid

Jackets/Outer Coverings over shields are mainly of PTFE (upto 12 mm OD); larger sizes are difficult with PTFE.  PVC or Silicone Varnished Fibre Glass or Polyurethane are available for such cases (or otherwise).