I understand that the snake should not have direct contact with the flexwatt but to be sure that the correct amount of heat is provided for a stable temperature i am considering putting the flexwatt inside the enclosure covered with either a ceramic tile or Linoleum and a couple inches of substrate. The snake would never have direct contact with the heating source but from what I've heard from people that use the 11" flexwatt, use of this product on the outside of the cage does not provide sufficient heat.