The MK4->MK4S Upgrade Kit contains everything you need to fully upgrade your stock MK4 3D printer to the new MK4S.

The upgrade is supplied as a kit - you need to assemble it yourself. 

This kit is for the xLCD version

The GPIO module (General Purpose Input/Output) is an optional add-on PCB that can be connected to the Original Prusa MK4/S, MK3.9/S, or MK3.5/S. It extends functionality by allowing you to control and receive input from external devices using GPIO pins and G-code commands.

Compatible with: 

MK4MK3.9MK3.5MK4SMK3.9S

This product is the replacement Hotend fan Noctua. It is ONLY compatible with the MK3/S/+. The MK2.5/S Rambo requires the v-cable adapter, the fan can NOT be connected to the MK2.5/S Rambo directly.

This product is the replacement part of the Dock Pin for the Original Prusa XL

XL

This product is the replacement hotend PTFE tube

ONLY compatible with the Mini/+

This product is the replacement PSU to Einsy power cable. It is ONLY compatible with the black housing PSU.

This product is the replacement IR filament sensor-Buddy board cable. It is ONLY compatible with the MINI/+.

Prusament PLA is an in-house-made filament at Prusa Research. The whole manufacturing process is closely monitored and tested - guarantee ±0.02mm precision and highly consistent colors.  You can inspect the parameters of every spool made at prusament.com. 

Prusament PETG is an in-house-made filament at Prusa Research. The whole manufacturing process is closely monitored and tested - guarantee ±0.02mm precision and highly consistent colors.  You can inspect the parameters of every spool made at prusament.com. 

Double-sided powder-coated Satin spring steel sheet for the Original Prusa Mini/Mini+.

Hotend Print Fan compatible with: 

MK3.9MK4XL

Linear bearing LM10UU

Compatible with: 

MINIMINI+MK3.9/SMK4/S

Idler Spring - for use across Most Prusa models except MK2/s and SL1/CW1

High Quality, Hardened Steel abrasion-resistant v6 style nozzles for 1.75mm filament.

This product is an optional accessory, compatible with: 

MK3.9MK4XL

Double-sided powder-coated PA Nylon spring steel sheet compatible with: 

MK3SMK3MK2.5SMK2.5MK2SMMU3MK3S+MMU2MK2MK4