Determining the exact model of your Prusa Printer is crucial for troubleshooting, upgrades, and finding the right parts. Prusa Research has released several iterations of their popular printers, and while they share similarities, key differences exist. This guide will help you identify your Prusa MK2, MK2.5, MK3, MK3S, or MK3S+ model.
The foundational MK2 and MK2.5 printers are visually distinct from the MK3 series due to their base frame construction and power supply. MK2 and MK2.5 models utilize a base frame constructed from threaded rod studding, often referred to as “all thread.” They also operate on a 12-volt power supply system.
Prusa MK2 and MK2.5 frame comparison showing the threaded rod construction, a key identifier for these Prusa printer models.
In contrast, the MK3 series printers, including the MK3, MK3S, and MK3S+, are built with a more robust aluminum extrusion base frame. This series also upgraded to a 24-volt power supply, offering increased power and performance.
Within the MK3 series, further distinctions can be made based on the power supply unit and extruder setup. The original MK3 printers were equipped with a silver-colored power supply.
Early Prusa MK3 power supply, silver color, a visual characteristic to distinguish it from later MK3 series Prusa printers.
Later iterations, specifically the MK3S and MK3S+, transitioned to black power supplies, often manufactured by Delta. Beyond the power supply color, the extruder assembly provides further clues. The MK3 extruder features two filament tension screws with springs, which press the Bondtech idler door against the filament. It also incorporated a vertical 4-wire laser filament sensor.
The MK3S model introduced a redesigned extruder. It utilizes a horizontal three-wire infrared filament sensor, typically mounted on a mostly black PCB. The MK3S also uses a 4-wire Pinda sensor and a single tension screw with spring for the Bondtech idler. Another key identifier for the MK3S is the presence of U-bolts securing the Y-axis bearings.
Prusa MK3S with black Delta power supply, a later revision in the MK3 series indicating MK3S or MK3S+ Prusa 3D printer.
The MK3S+ model represents the latest evolution in this series. It incorporates a red PCB infrared filament sensor in a horizontal configuration. The SuperPinda probe now utilizes three wires. Further refinements in the MK3S+ include sheet metal bridge clamps for the Y-axis bearings and printed clamps replacing cable ties to secure the Y-axis rods. The MK3S+ also retains the black power supply from the MK3S.
Finally, a quick and reliable method to confirm your Prusa printer model is to check the firmware version displayed on the LCD menu. Navigating to the “bottom option” in the LCD menu will typically reveal the currently loaded firmware, which directly corresponds to your printer model. By examining these physical characteristics and checking the firmware, you can confidently identify your Prusa printer model.
