Prusa Prusa MK4 to MK4S Upgrade kit, xLCD new

The Prusa MK4 to MK4S Upgrade Kit is a retrofit kit that brings an existing Original Prusa MK4 up to the full feature set of the MK4S. The kit includes all mechanical and electronic components required for the upgrade, including a high-flow nozzle, a new cooling system and a Wi-Fi module. It is designed for existing MK4 owners who want to add higher printing speeds, improved cooling and greater connectivity without buying a completely new printer.

Significantly higher printing speeds with Input Shaper and Pressure Advance

With the upgrade, the printer uses a native implementation of Input Shaper and Pressure Advance to reduce resonance in the motion system and control filament flow more precisely. In combination with the new high-flow nozzle, this doubles the printing speed compared with the MK3S+, while keeping operation noticeably quieter.

360° cooling system for clean overhangs

Instead of conventional fan covers, a newly developed turbine with a revised fan shroud is used. The airflow has been optimised through flow simulations so that cooling air is directed precisely at the print and is not blocked by the object itself. This makes it possible to print overhangs of up to 75° reliably without additional support structures, reducing both printing time and material consumption. The weight of the Nextruder remains virtually unchanged.

High-flow nozzle as standard

The kit includes a brass Prusa Nozzle with CHT technology and a diameter of 0.4 mm. Compared with the standard MK4 nozzle, the flow rate improves by 50 to 114%, depending on the material and nozzle diameter. This allows familiar standard filaments to be printed faster, without the need for special high-flow filaments.

Greater connectivity with Wi-Fi and NFC

The kit includes an additional Wi-Fi board and an NFC antenna, allowing the printer to be connected easily to the optional Prusa app for iOS and Android with an NFC tap. The app can be used to keep track of several printers, start, pause or stop print jobs and print projects directly from Printables. Users who prefer not to use the app can ignore this function entirely, as it is optional.

New components made from Prusament PC Blend Carbon Fiber

As part of the upgrade, several mechanically stressed Nextruder components are replaced with parts made from Prusament PC Blend Carbon Fiber or with injection-moulded versions. This improves the stiffness and durability of the affected components compared with the original MK4 setup.

Included in delivery:

• 1 x Prusa Nozzle Brass CHT, 0.4 mm
• 1 x high-performance 360° cooler with fan shroud
• Nextruder components, including PCCF printed parts
• 1 x Wi-Fi board with NFC antenna
• Cover for xLCD and Nextruder
• Silicone cover for the heater block
• Screws and additional mounting material