Take the blade that has the long center slit that is open at the bottem and insert it through one of the slots in the ferrule until its center slit lines up with the the other slot in the ferrule. Then insert the other blade through the other slot in the ferrule and through the center slit in the first blade. Slip the metal washer up over the threads and push the blades forward until they seat firmly in the tip. Screw it on your arrow. Sounds harder than it actually is. I didn' t find the assembly of these to be that difficult.