Amazon.com: LEGO Technic 4 pcs NEW YELLOW MINI PNEUMATIC PISTON CYLINDERS Air pressure Pump pack lot set switch hose small little robot robotics : Toys & Games
6 Lego Black Yellow Flexible Hose Connector Black Ends Part 73590 Tabless(LS168) | eBay
LEGO part 73590c03b - Yellow Hose, Flexible 8.5L with Tabless Ends Black (Ends different color than Tube, ends not removable) at BrickScout
0.08'' x 0.16'' x 3.3ft Tubing Tube Air Hose Pipe for Pump Transfer Silicone Yellow 1pcs - Walmart.com
Bricker - Part LEGO - 73590c01b Hose, Flexible 8.5L with Tabless Ends Black (Ends different color than Tube)