With the E3D Revo CR upgrade kit you'll be able to change the nozzle without tools. The improved heatsink also ensures that printing can be done with a maximum temperature of 300ᵒC. The set includes a 24V Revo CR hot end with an interchangeable 0.4mm nozzle.
The E3D Revo nozzle has its own heat break. This means that it is not necessary to tighten the nozzle at a high temperature. Because each Revo nozzle diameter has its own colour, you can quickly see which nozzle diameter you have in the hot end.