Hola tendrán en tamaño del bloque multinivel de la falcón 2 no encuentro el mío y necesito cortar 3 mm
You are talking about the tool that allow you to set the distance between the laser module and the piece you want to cut/engrave? You should contact the palce where you bought the Falcon from.
Also, you can search on Thingiverse.com or Printables.com - there are plenty of 3d models to print - you just need to find someone that could print one for you.
Good luck!