3DSolex Matchless Everlast 1.75mm Nozzle

No, Only diamonds last forever.

The tip of these nozzles has a hardness many, many times that of steel,  even hardened steel and titanium.

On a non-linear scale of hardness  from 0 – 10, where brass has 3-4 and steel hardness 5 and up, the EVERLAST tip has a hardness of 9.  Diamond is 10.

It is unlikely that you will print much material which can destroy the tip.  However, you will be able to slowly destroy the inside of the nozzle. 

With the exception of the 0.25mm size, all EVERLAST nozzles implement the patent pending “core heating” system, which allows for a faster melting of plastic. This system is the only known way to achieve high printing speeds with nozzles larger than 0.60mm on FFD printers.

This internal structure will wear ut over time, but much more slowly than the tip of a standard nozzle. The reason it is slower is because the tip in standard nozzles is mostly ( more than 90%) destroyd by the rubbing in the hardening deposited material, not much by the internal flow of the melted plastic. 

As the core heating (called MATCHLESS) of EVERLAST nozzles wears out, they eventually become more like normal nozzles on the inside.

As long  as the Matchless part of the EVERLAST is a little intact, you can print faster, and at lower temperature than with any other nozzle.

In most cases, as nozzles are worn on the inside (standard nozzles or Matchless ones, like the EVERLAST), the abrased material is carried out with the plastic in microscopic pieces over time. With Matchless ones, in some rare cases a piece of the core heating system can break off and find its way to block the exit hole (this can never happen with a standard nozzle, of course). 
This is  repaired by performing a “cold pull”..  Video here..

Cold pulls are always advised from time to time regardless of nozzle in use, and it is a MUST when changing between materil types; PLA residue will burn and stick to inside walls when printing ABS in the same nozzle. Always perform several cold pulls and you will be fine.

EVERLAST nozzles come in sized from 0.25 to 0.80 mm.

Some fibre materials need a larger size than the industry standard 0.40mm nozzle. Some like to print in small detail, some need a large nozzle to print large objects quickly.

With the EVERLAST 0.80mm, you will. be able to finish a 16h print/0.40mm nozzle in 4-5 hours instead.
You can use the same low layerheight 0.10mm, or you can go all the way up to 0.6mm layer height.

It isn`t expensive. 

Many materials on the market today will destroy your Ultimaker Core in a few hours !

The EVERLAST nozzle will print continuously  for weeks or months without being destroyed.
The nozzle is also tough to manufacture.

There are customers who “earned” the cost of the nozzle back in a short day.