Aluminum and one cool Delta based design from creator of H-bot. You can find details and construction details on:
http://translate.google.com/translate?hl=en&sl=pl&tl=en&u=http%3A%2F%2F3d-printers.pl%2Fogolne%2Faluminatus-trident-buildlog%2F
http://translate.google.com/translate?hl=en&sl=pl&tl=en&u=http%3A%2F%2F3d-printers.pl%2Fogolne%2Faluminatus-trident-buildlog%2F