The major difference between Neptune 4 and Neptune 3 series is below:
A. Neptune 4 series has various extended ports to support remote control - LAN, USB-C, USB 2.0
B. Neptune 4 series is equipped with a robust cooling system with 4x individual blowers which makes high speed printing possible.

The major difference between Neptune 4 and Neptune 4 PRO is below:
The Pro version has segmented heat on the build plate.
The Pro version has metal linear rail on X axis instead of the rubber wheels.

Same day pick-up available or fast shipping from Las Vegas Nevada 89103

This listing is a DIY 3D printer that requires assembly, calibration, modifications & dedication. It’s great only for who love to do homework, research and learn on YouTube as well as on users communities. Please only buy this model if you ENJOY this process. 

Open-box A+ -> The item is in like new, never used/assembled condition. It's returned due to buyers' remorse or fulfillment error. It may only show sign of repackaging due to our inspection service (opening the box, taking photos, recording serial #, classifying grades). It's sealed, packaged in the original factory condition with ALL original factory parts/accessories in inspected new or like new condition.

Pre-owned with Warranty -> backed with 30-day warranty by our store - you will have a FULLY FUNCTIONAL UNIT OR YOU GET FREE REPLACEMENT (parts/units). It was inspected, cleaned, repaired to full working order and is in overall good pre-owned condition. It WILL contain aesthetic signs of wear/teas/scratches (especially on the tank/lid). This item may be repackaged.
Damaged as Parts Only (fix-up DIY projects) ->  Most units in this grade have 1 or more major defects. They might be missing components, parts, accessories, hardware, or not intact.

• Please leave a note with your order if you are looking for a donor unit for specific parts. We will pick one from the lot that serves your needs, or pick one that you know how to fix (notes are appreciated).
• If your order is for two units or more, we will automatically pair the defects so that you can use one to fix the other one and make one fully functional unit. Our store warranty is that customers will make one fully functional unit for every two units purchased, or you will get free replacement parts for your fix-up projects.

Most commonly seen damage on FDM units (might contain one or ALL):
A. wobbly/deformed X cartridge/Y plate/Z lead screws
B. Not homing properly/limit switch error/stepper motor wiring
C. bad thermistor(re-wiring/replacing required) jammed/clogged hotend
D. Bad board, firmware issues, not power on etc.

* touch screen controllers are interchangeable among ALL these 7 models (firmware reflahsing is required)
Neptune 3 Pro, 3 Plus, 3 Max, Neptune 4, 4 Pro, 4 Plus, 4 max

* main boards are interchangeable throughout the series:
Neptune 3 series: 3 Pro, 3 Plus, 3 Max - same main board (firmware reflahsing is required)
Neptune 4 series: 4, 4 Pro, 4 Plus, 4 max - same main board (firmware reflahsing is required)

* hotend assembly is interchangeable throughout the generations
Neptune 3 series: 3 Pro, 3 Plus, 3 Max - same hotend (just plug-in, no action required)
Neptune 4 series: 4, 4 Pro, 4 Plus, 4 max - same hotend (just plug-in, no action required)