This is a cache in the Insecta Series. Each cache is related and when the series is completed hints in the cache can lead you to an additional mystery cache.
This cache is named after a bug we tend to tolerate. It is the most common fly species found in houses. Adults are gray to black, with four dark, longitudinal lines on the thorax, slightly hairy bodies, and a single pair of membranous wings. They have red eyes, set farther apart in the slightly larger female. (Wikipedia).