This Creality K1 Nozzle Kit contains 8 nozzles made of premium material. They ensure a smooth inner wall, smooth extrusion and even supply of filament. You can also easily print filaments at a higher temperature. The 4 nozzles are made of a copper alloy. The good thermal conduction ensures that they heat up gradually. The volume is twice as large as that of standard nozzles, making high-speed printing possible. The nickel layer ensures that filaments stick less. The 4 hard steel nozzles can withstand frequent use. They have better anti-oxidation and an advanced heat treatment process, which together ensure a longer lifespan.