The Original Prusa MK4S is a fully assembled, high-performance 3D printer featuring the direct-drive Nextruder, automatic Load Cell first-layer calibration, Input Shaper, a high-flow 0.4 mm CHT nozzle, and powerful 360° part cooling.

With a 250 × 210 × 220 mm build volume, broad filament compatibility, and optional MMU3 multi-material support, the MK4S is an excellent choice for home users, schools, businesses, makerspaces, and professional workshops.

This is the fully assembled version — no printer assembly is required.

Original Prusa MK4S

The Original Prusa MK4S builds on Prusa’s proven open-frame 3D printer platform with faster printing, improved cooling, automatic calibration, and a high-flow extrusion system.

Its direct-drive Nextruder provides precise filament control, while the integrated Load Cell sensor automatically calibrates the first layer without requiring manual Z-offset adjustment.

The MK4S is designed to deliver reliable results across everyday, flexible, and engineering-grade filaments while remaining easy to maintain and service.

Fully Assembled and Ready to Print

The Original Prusa MK4S arrives fully assembled and factory tested.

After unpacking the printer, complete the initial setup and automatic calibration, load filament, and begin printing.

The assembled MK4S is particularly well suited for:

• Businesses and professional workshops
• Schools and universities
• Makerspaces and libraries
• Print farms
• Product development
• Engineering and prototyping
• First-time Prusa owners
• Users who want minimal setup before printing

Fast, High-Quality Printing

The MK4S combines Input Shaper, optimized firmware, improved cooling, and a high-flow nozzle to reduce print times while maintaining excellent dimensional accuracy and surface quality.

The motion system is tuned to minimize vibration during faster moves, allowing the printer to complete parts more quickly without sacrificing detail.

360° High-Performance Cooling

The MK4S uses a powerful turbine fan and redesigned cooling system that directs airflow around the nozzle from all directions.

Improved cooling is especially useful for:

• High-speed PLA printing
• Bridges
• Overhangs
• Fine details
• Small layers
• Decorative models
• Functional parts

The enhanced cooling system also helps reduce the amount of support material required on suitable models.

High-Flow 0.4 mm Prusa CHT Nozzle

The MK4S comes equipped with a 0.4 mm high-flow Prusa CHT brass nozzle.

The increased melt capacity allows the printer to maintain higher extrusion rates during fast printing while still providing the accuracy expected from a 0.4 mm nozzle.

This makes it suitable for both detailed prints and faster functional parts.

Nextruder Direct-Drive Extrusion

The MK4S uses Prusa’s Nextruder direct-drive system with a 10:1 planetary gearbox.

The short and controlled filament path provides accurate extrusion across a wide variety of filament types, including flexible materials.

The Nextruder also features an all-metal hotend and quick nozzle-change system for easier maintenance and nozzle replacement.

Fully Automatic First Layer

An integrated Load Cell sensor allows the nozzle itself to detect the build surface.

The printer automatically performs mesh bed leveling and first-layer calibration without requiring manual Z-offset adjustment.

This makes it easier to switch between compatible spring-steel print sheets while maintaining a consistent first layer.

250 × 210 × 220 mm Build Volume

The MK4S provides a practical 250 × 210 × 220 mm build area suitable for a wide range of applications.

Typical uses include:

• Functional parts
• Engineering prototypes
• Replacement components
• Household items
• Educational projects
• Models and miniatures
• Jigs and fixtures
• Product prototypes
• Small production runs

Wide Material Compatibility

The MK4S supports a broad selection of standard and engineering filaments.

Common materials include:

• PLA
• PETG
• TPU / Flexible filament
• PVA
• PC / Polycarbonate
• PP / Polypropylene
• CPE
• PVB

With the appropriate enclosure and filtration, the MK4S can also be used with materials such as:

• ABS
• ASA
• HIPS
• PA / Nylon

The hotend can reach temperatures up to 290°C, while the heated bed can reach up to 120°C.

Optional MMU3 Multi-Material Printing

The Original Prusa MK4S is compatible with the optional Prusa MMU3 Multi Material Upgrade.

MMU3 allows the printer to automatically switch between as many as five loaded filaments during a print.

This enables:

• Multi-colour models
• Multi-material parts
• Automatic filament switching
• Decorative colour changes
• Support-material workflows

MMU3 is sold separately.

Optional Original Prusa Enclosure

For materials that benefit from a more stable printing environment, the MK4S can be installed inside the optional Original Prusa Enclosure.

An enclosure can help:

• Reduce drafts
• Stabilize chamber temperatures
• Improve ABS and ASA printing
• Reduce printer noise
• Support optional air filtration
• Protect the printer in classroom or workshop environments

The enclosure is sold separately.

Connected or Completely Offline

The MK4S can operate without an internet connection.

When connectivity is desired, the printer supports:

• Wi-Fi
• Ethernet
• NFC-assisted Wi-Fi setup
• USB
• Prusa Connect
• Prusa mobile app

The Wi-Fi module can also be physically removed for environments with stricter security requirements.

Open and Serviceable Design

The MK4S retains Prusa’s accessible open-frame construction.

Mechanical and electronic components can be reached easily for maintenance, inspection, and replacement without disassembling a sealed enclosure.

This makes the MK4S particularly suitable for users who value long-term serviceability and repairability.

UL GREENGUARD Certified

The Original Prusa MK4S carries UL GREENGUARD Certification, making it particularly relevant for use in environments such as:

• Schools
• Universities
• Libraries
• Makerspaces
• Offices
• Institutional facilities

Key Features

• Fully assembled and factory tested
• 250 × 210 × 220 mm build volume
• Nextruder direct-drive extrusion system
• 10:1 planetary gearbox
• 0.4 mm high-flow Prusa CHT brass nozzle
• 360° high-performance part cooling
• Automatic Load Cell first-layer calibration
• Automatic mesh bed leveling
• Input Shaper
• 290°C maximum nozzle temperature
• 120°C maximum heatbed temperature
• Magnetic heated bed
• Removable PEI spring-steel print sheet
• Filament sensor
• Power-loss recovery
• 3.5-inch colour display
• Wi-Fi connectivity
• Ethernet connectivity
• NFC-assisted setup
• USB printing
• Prusa Connect support
• Optional MMU3 five-filament system
• Optional Original Prusa Enclosure
• Open and serviceable construction
• UL GREENGUARD Certified

Technical Specifications

Supported Materials

The MK4S supports a wide range of filament materials including:

• PLA
• PETG
• TPU / Flex
• PVA
• PC
• PP
• CPE
• PVB

With a suitable enclosure and filtration:

• ABS
• ASA
• HIPS
• PA / Nylon

What's Included

• Original Prusa MK4S fully assembled 3D printer
• 0.4 mm high-flow Prusa CHT brass nozzle
• Removable PEI spring-steel print sheet
• USB drive
• Printer accessories and tools
• Documentation