It was always amusing to see Les Stroud not bring a sheath knife on Survivorman. Since the cult of the survival knife means asking 'what's the best knife?' is guaranteed to get a massive amount of replies. Oddly now he has a knife to sell (see the 'Les stroud reviews Doug and Bears kits thread', he now thinks one is essential :-)

But is it:

https://youtu.be/vJS1SepHop0