That ebay ad seems to be for a tough rubber extenson cable with plug and socket, I'm a bit slow, but I can't see a "heat resistant" in it yet, it just looks like a kind of tough flex.
some gaps in my knowledge especially in tech terms.
Edited to say no, Hedi appears to be the manufacturer, it's tested and certificated to some standard or other, I'd guess the ref no means 1.5mm. It's obviously flexible so must be stranded. I see no reference to armour or heat resist, or power handling, though that might be in the referenced standard. They're selling 25metres for about a tenner plus P&P, can't be anything special. And they're selling it in home and garden, not business and technical