Fraternitas Rosae Crucis (Fraternity of the Rosy Cross or FRC) is a Rosicrucian fraternal organization founded by Paschal Beverly Randolph in 1858, and is the oldest Rosicrucian Order in the US. They also operate Beverly Hall corporation and the Clymer Health Center in nearby Quakertown, Pennsylvania.
It claims to be the "authentic Rosicrucian Fraternity that was first instituted in Germany in 1614".
Read more about Fraternitas Rosae Crucis: History, Supreme Grand Masters