Alternative to LEGO Hose, Rigid 3mm. Compatible Flex Tube for Brick Models - Etsy
Amazon.com: TEESE 21pcs Pneumatic-Kits Compatible with Lego-Technic-Parts, Piston-Pressure-Rod, Air-Pump-Cylinder-Hose, MOC Car Truck Replacement Parts : Toys & Games
Hose, Ribbed 7mm D. 9L / 7.2cm : Part 78c09 | BrickLink
LEGO Sets with Part 75 Technic Flex-System Hose, Rigid 3mm D.
Lego Hose Flexible Yellow Tube 8.5L With End Tabs | eBay
LEGO part 73590c01a - Light Gray Hose, Flexible 8.5L with Tabless Ends (Ends same color as Tube) at BrickScout