What is +7 trial set?

As an AI language model, I don't have any context about what topic you specifically want me to give information about the "+7 trial set." However, I can tell you that the term "+7" is generally used as a reference to equipment or accessories that are designed for people who are seven feet tall or taller. As for the term "trial set," it could refer to a set of products that are given out for trial purposes or a set of equipment that is rented out for a limited period of time for testing or evaluation. It would be helpful if you could provide more context or information about what exactly you want to know about the "+7 trial set."