Hand Piston Pump 13 August 2017, 19:00 Sorry, your browser doesn't support embedded videos, but don't worry, you can download it and watch it with your favorite video player! 3a.avi Uploaded on 26/08/2014 Green double cam lever controls two pistons. Spring ball valves are operated automatically thanks to fluid pressure. The arrows show fluid flows. « previous mechanism Toggle Linkage next mechanism » Unfallen Beetle load comments Please enable JavaScript to view the comments.