This great kit consists of 5 nozzles, for the UM2+ / Matchless / Olsson Block / E3D: 0.25-0.40-0.60-0.80 ICE Brass nozzles + 0.40 Everlast Ruby All the nozzles are brass nozzles. Except for the EVERLAST Ruby 0.40, they are coated with a hard and slippery material which makes cleaning a lot easier, and helps preventing plastic stick and being carried around the print. These nozzles are standard nozzles except the Everlast which has the “Matchless” design of heating the filament. This enables higher printing speeds and / or lower temperature, which again helps against dripping. The ICE nozzles look a bit irregular on the surface due to the treatment, but this quickly evens out and does not affect printing. The nozzles have a run-in period of 2 hours at 200C-225C , to harden, tempering the surface. After that they should be used at mazh 265C. Higher temperatures than 265C will destroy the treatment and the nozzle is the just like any other nozzle! ONLY the Everlast is recommended for abrasive materials, the other nozzles will wear out quickly.