Prusa Nextruder Hotend brass - 0.4 mm is a fully assembled melt zone for the Nextruder print head. It includes a 0.4 mm brass nozzle, heater block, 40 W heater cartridge and NTC 100k thermistor - just swap it for the old hotend and continue printing. Compatible with MK4/S, MK3.9/S, XL, CORE One/+ and CORE One L printers.

Original part directly from Prusa Research

The hotend is supplied fully assembled by the manufacturer, so there is no need for manual assembly of individual components. The brass nozzle is seated precisely, threads are tightened to torque according to Prusa Research specifications, and the entire assembly has passed outgoing inspection. No improvisation - service and maintenance can be done in just a few minutes.

0.4 mm brass nozzle for everyday printing

The 0.4 mm diameter is the standard choice for most user projects - a balanced ratio between print speed, detail and stability. Brass conducts heat excellently and is well suited for non-abrasive filaments such as PLA, PETG, ABS, ASA or flexible filaments.

40 W heater cartridge for fast heat-up

The package includes a 40 W heater with 120 mm wiring. The output is sufficient to stably maintain high temperatures even during fast printing with high filament flow. The extruder heater block ensures even heat distribution and minimises temperature fluctuations.

Precise NTC 100k thermistor

An NTC 100k thermistor with 115 mm wiring is used for temperature sensing. It reacts quickly to temperature changes and provides the firmware with accurate readings, which keeps PID control stable and prevents the printing temperature from drifting across a wide range.

Wide compatibility with Prusa printers

The hotend is intended for the MK4, MK4S, MK3.9, MK3.9S, XL, CORE One, CORE One+ and CORE One L models. Warning - it cannot be used on older printers with a V6-type extruder such as MK3S, MK3S+, MINI or MK3.5. Before purchase, make sure your printer uses the Nextruder platform.

Easy nozzle replacement

Replacing the entire hotend is faster and safer than replacing the nozzle alone - you eliminate the risk of damaging the heater block threads or the thermistor. The procedure is described in detail at help.prusa3d.com, where you can select your specific printer model. For printing with abrasive materials such as carbon or nylon, we recommend choosing the hardened variant - see the nozzles category.

Ready for the load cell sensor

The hotend is designed to work with the Nextruder's load cell sensor - first layer calibration is a matter of seconds and you do not need to fine-tune it manually. After replacement, we recommend running the Loadcell test and First Layer Calibration procedures.

Package contents

1x Prusa 0.4 mm brass nozzle (pre-mounted), 1x extruder heater block, 1x 40 W heater cartridge with 120 mm wiring, 1x NTC 100k thermistor with 115 mm wiring. Everything is supplied fully assembled and ready for installation.