Sale of assembled full power lasers

Question regarding the sale of full power lasers in the United States. I plan to get working with a foreign company in China to start producing my own laser design, it is a mounted laser designator and illuminator in one with a power of 50mw and 150mw respectively. The company told me, the design would be automatically copyrighted by me since I am the "inventor" or designer behind it, it was my idea to create it. They will be designing the PCBs for it to my requirements, I will be designing the actual housing and other components, but they will produce and assemble everything overseas and ship me assembled units. The lasers would then be sent to me as I order them, and then I would sell them in the United States, either on my own website or ebay and other places. They also said I would be the only one they will be selling this product to and nobody else would be able to buy it from them directly. What I would like to know is whether everything I described is legal to do, specifically t