What size is this unit T4A360GKD300?

The unit T4A360GKD300 typically refers to a specific model of a heating or cooling unit, but to determine its exact size, you would need to consult the manufacturer's specifications or product documentation. Generally, model numbers like this include information about capacity in BTUs or tons, which indicates the unit's size. If you have access to the manufacturer's website or product manual, it will provide the most accurate size information.