BNTECHGO 20 Gauge Silicone Wire Kit 10 Color Each 10 ft Flexible 20 AWG Stranded Tinned Copper Wire

Q: What is the outside diameter of the wire including coating?

The O.D. measures .051" (1.30mm). I have used a lot of this wire for high flex test leads in test fixtures. It strips easily, is durable, solders easily and is about as flexible as possible. A really nice side benefit is that the insulation does not melt/burn while soldering like PVC does. I highly recommend it.

Q: What about car stereo applications? car audio speakers and such...will be near heater and ac ducts....

I bought some of this wire,and must say,it is sum of the best wire out there. U shudnt run into any problems with wire being next to heater vent. Made from very good silicone. I use it to build quadcopter with. Silicone does not melt when I solder wires. But it only comes in certain lenghts. But it is sold else were as well ,prolly longer lenghts.