The type of IR lamp I have is the same as used in reptile cages and gives off no light at all, well not as we know it. I believe it’s the same IR as used by the military for night vision? My research also showed this to be the best type of IR to use in conjunction with PE. As I understand it the temperature needs to be pushing 45 degrees C for it to be of benefit. The tissue will stretch that bit further, but doesn’t return entirely to its previous condition if held extended while the heat source is removed and the unit rapidly cooled.
seahorse