Fichtel u. Sachs Torpedo Freilaufnabe Woran erkennt man Originalteile Info-Blatt 1926 - Velopedia
Torpedo-Freilaufnabe – Wikipedia
The engineer Ernst Sachs in 1903, in his small factory in Schweinfurt, invented the Torpedo-Freilaufnabe, which in itself combined drive, freewheel, backpedal brake and from 1905 even the gear shift (undated photo