What's the requirements to visit a factory in China , I'm a holder of a Trinidad & Tobago passport with US visa, I also have invitation letters from this factory.

Ryan, you need to provide more documents: invitation letter from duly authorized Chinese unit. You can ask the factory to help acquire this.

Thanks for the quick reply, one more question, apart from this letter what is the process thereafter?

Assuming I am in the US ( Florida) would i need to come back to Trinidad to process this? or can it be done thru the Trinidad embassy in Florida or the Chinese embassy in Florida?

Hi, according to the rules, you are possible to apply it in USA at the local Chinese consulate in Houston. You can contact this consulate for confirming this.

For other documents, they are basic ones, including your valid passport, an application form and a recent taken photo.

Only in Huston? no other offices lets say in Florida?

It is a pity that there is no office in Florida.