This replacement V6 nozzle for E3D hot ends is made of hardened steel. Hardened steel nozzles are suitable for some highly specialised materials, where a standard (brass) nozzle is at risk of corrosion. The hardened nozzle provides the same performance as the brass version, but has a longer delivery time than the standard brass version.
This nozzle has an opening of 0.5mm (marking #6) and is suitable for filament with a diameter of 3mm.