These were inspired by G1 Wheeljacks cartoon shoulder launcher and has a 4mm Peg for mounting. Perfect for Sideswipe, Sunstreaker, or Punch/Counterpunch who have a 4mm mounting hole on their shoulders.
(my disclaimer) normally before I release anything on Shapeways I always get a prototype to ensure all my designs are functional. This is the one time I did not. But I'm pretty positive it should work. I just dont like my buyers to feel like they wasted their money on my designs due to my own mistakes. Enjoy!