What is this tool?

It is a heat gun tool. I used a similar model called a ht-900. You can actually solder with it. Used in areas with explosive fumes. I am sure you can plastic weld with it also. The amount of heat is adjusted by the air flow. Slower hotter faster cooler. Great find. Start the air flow first before power and kepp the air flow on after you take the power off or the heating element will burn out and they are not cheap. Great score!