11 dart capacity, May need to be broken up to print on smaller printer beds. Here is a hardware list as can be ordered from McMaster-Carr. These parts can be purchases at your local hardware store usually, but I would still visit McMaster-Carr's site and print out the product details for each of these part numbers to take with you so that you can ensure you are matching specifications. Also I have updated the model to better suit some of the hardware as when i imported the solidworks files they were a bit off of what i had intended. Lastly I have included a render with the hardware to show rough orientation, when I get a chance, (and have re-installed 3d studio max) I will create animated assembly instructions. http://www.mcmaster.com/ Trigger catch Guides 4x McMaster-Carr Part number 90910A669 Trigger Catch Pins 4x McMaster-Carr Part number 98105A050 Trigger Catch Springs 2x McMaster-Carr Part number 9434K49 Plunger Cap 4x McMaster-Carr Part number 90128A250, 4x McMaster-Carr Part number 95479A111 Plunger Head 1x McMaster-Carr Part number 91355A168, 1x McMaster-Carr Part number 90545A009 Plunger Spring 1x McMaster-Carr Part number 9637K26 (cut to length) Plunger O-ring 1x McMaster-Carr Part number 9396K19