The smaller the nozzle, the more detailed the final product can be. However, when speed of printing is of greater importance than detail, a larger nozzle may be preferable.
2.1.75mm filament diameter
The 1.75mm filament diameter is gradually overtaking the previous 3mm standard. The 1.75mm filament feeds into the printer with greater ease and allows for more detail in the printing process.
3.number of extruder heads
More extruder heads allow you to use different colors and different types of material at the same time. A second extruder is also required to build PVA/PLA support structures around items as they are printed.
The speed at which 3d objects are printed, measured in millimeters per second.