It is an upgrade kit to change entry level Ender3 V2 or Ender3 Pro (only compatible with these two printers) to professional level VORON E3-Switchwire, so that can change printing speed from 80mm/s to 200mm/s, and can print ABS, PA, etc. filament.
Specification: Ender3 V2/Ender3 Pro 3D Printer Upgraded Kits Voron E3-Switchswire Stealthburner Pro Conversion Switchwire Kit DIY 3D Printer