I think these guys are the originator of all vaporizers that are like this. These units last literally forever because the company still fixes them even after mine was 10 years old. I use portable vaporizers but half the time I need to clean them or replace parts, so I fall back on my VB model. It gives me incredible vapor every time. I hear that VB is a USA company and has done extensive testing on their parts to make sure we are not being exposed to toxins.