The New Nylgut is nor common Nylon or Carbon (Flurocarbon fishing line or PVDF), or a mix of them. It is a plastic compound of three different components.
Compared to Nylon, the New Nylgut produces a better sound and stays in tune better, this because the moisture absorption is less than 0.1% against the 2.0% of Nylon normally employed for the musical strings (i.e. Du Pont Tynex polyamide 6-12).
Due to the higher density, similar to that of pure gut (1.30 gr/cm3), the New Nylgut produces a better sound than Nylon and it is not so metallic like those of the so-called 'Carbon' (Fluorocarbon) PVDF strings. In other words, the New Nylgut is probably the first genuine synthetic gut in the world.
A better sound than Nylon or PVDF, similar to the genuine gut strings.
A more accurate fret-intonation due to the well gauged material.
A very stable intonation under moisture changes.