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.
56% have it
2. has an external memory slot
The device has a standard memory slot (such as an SD or micro SD card slot) so that you can either extend the internal storage with affordable memory modules or you can retrieve data, such as photographs, easily from a memory card.
35% have it
3. Has a heated build platform
A heated build platform helps keep the lowest levels of a print warm as the higher layers are printed. This allows the overall print to cool more evenly.
More extruder heads will allow you to use different colours or 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.