High Tech Parts Blue Pneumatic Pump Small (6L) V2 with Reinforced Cylinder 19475 2793C01 1x5/2x6 Compatible with MOC 8800 Blocks|Blocks| - AliExpress
LEGO Pneumatic experiments - YouTube
LEGO MOC compact pneumatic pump by Green parrot | Rebrickable - Build with LEGO
Goshfun 19Pcs 10-Kinds MOC Pneumatic Parts Bricks with Air Pump Push Rod Switch Piston Air Pipe, DIY Small Particle Stem Building Blocks Toy Set Compatible with Lego, Random Color of Air Pipe