An exothermal vaporizer is provided. The exothermal vaporizer has a body including an air and vapor mix port, a fluid inlet port in communication with a reservoir, an air inlet, and a wicking material. A mouthpiece is coupled to the body and a temperature indicating cap is removable from the body. A counter flow design exothermal vaporizer, a modular exothermal vaporizer, and a vaporizer which is adjustable to modulate and/or regulate the flow ratio of dilution air and produced vapor are also disclosed.
