Ender 3 v2 all metal hotend upgrade - NotEnoughTech
Bowden Tube (What it is, Prevent Clogging, and Upgrades)
Capricorn PTFE Tubing - Filastruder
TLDR at the bottom. - 3D Printing - Maker Forums
Tough Tube - High Temp, Tight Tolerance PTFE Tubing - TH3D Studio LLC
Amazon.com: Authentic Capricorn PTFE Bowden Tubing (1 Meter) XS Series for 1.75mm Filament with PTFE Teflon Tube Cutter and Upgraded PC4-M6 and PC4-M10 Pneumatic Fittings with Metal Teeth and 2 Blue Collet