What Are the Differences? Prusa MK3.5S vs MK3.9S vs MK4S
The MK3.5S kit is the most cost-effective option to upgrade your MK3S/+ with plenty of new and useful features, including doubled printing speed thanks to Input Shaper and Pressure Advance support.
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MK3.9S contains everything from the MK4S except for the X/Y/Z motors (Nextruder motor is included).
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The full upgrade contains the MK4S’s new X/Y precise motors (400 steps, 0.9°per step).
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