Pneumatic controled Lego Technic Great Ball Contraption (GBC) module by Parda.

It has 3 pairs of sinchroniced pneumatic cylinder-valves who control another pair in the 1-2-3 order as the name of the module is.

Feeded by a independent compressor powered by a Power Functions M motor (PFM) and two minipumps that allow the module perform 10 cycles per minute.

Find more information, GBC modules and lots of other Lego Technic stuff at:

http://technicdelicatessen.blogspot.com/