An easy to assemble and adjust catapult. Can use one or more rubber bands depending on the strength you want. Has a catch trigger and moveable stop to adjust the throw.  I press fit the trigger first then put in the round pieces into one side of the frame.  Next place the other frame on and finally fit the bottom plate dovetails.  I also put a bit of CA glue on the bar holding the latch after completing the rest of assembly so it would stay in the correct orientation.  Hope you enjoy.