Poseable hands for ROTF Leader Class Optimus Prime. The wrist and thumb are on a ball joint, the rest of the fingers are articulated on each phalanx (the palm also has some space to make 5 mm weapons fit better in the grip, just like the custom blaster that I also designed and you can find in this site). The pieces just need to get assembled (no glue needed). The file contains one full hand (wrist, palm and fingers), so just mirror it to print the other. You will need to dissasemble the forearm to change the original hands (it's not difficult, but be careful with the springs for the blades).
I must admit that the final stage of the transformation from robot to vehicle mode becomes a bit difficult with these hands attached, but you can make them fit well enough (closing the fists and accomodating them) for having just a very tiny gap with the front grill. Also, you can just detach the hands from the wrist ball joint to make the assembly fit better. I already adjust the wrist size, but making the hand a bit smaller just doesn't fit the figure's scale.