Frequencies located just above a communication box on a Sectional Aeronautical Chart are used for which type of facility?

Frequencies situated just above a communication box on a Sectional Aeronautical Chart are indeed associated with Flight Service Stations (FSS). FSS facilities provide pilots with a variety of services, including weather briefings, flight plan services, and information about airspace and airport conditions.

The communication box format helps pilots quickly identify the relevant frequencies for contacting these stations. By being at a specific location on the chart, these frequencies make it easier for pilots to obtain timely information and support during their flights.

In contrast, frequencies related to other facilities like Air Traffic Control (ATC), Automated Weather Observing Systems (AWOS), and tower communications are typically organized differently or are located elsewhere on the chart, which is why they would not match the description given in the question.