Originally Posted by Harhir

Slight correction: SRAM not equals SRAM.

Originally Posted by Harhir

SRAM also sold the older style 3x7 hub (Sachs) and branded it as SRAM Spectro 3x7. They have a different housing but are almost identical inside expect the clutch which had 6 claws in the older Sachs model and then 4 claws in the newer SRAM models.
But agreed the SRAM dual drive is completely different from the SRAM/SACHS 3x7. They are not compatible.

One more thing: The chains for the 3x7 are no longer available. I even can no longer find them in Germany. One can still buy the chain for the 3 speed where the pin is too short for the 3x7 or the chain for the 5 speed (left side) where the pin is too long. I need to try if I can use a 2mm die to extend the thread on the longer pin and then cut it to the correct length.