You're confusing yourself.
It's purely how lens manufacturers describe the shutters. Voigtlander clearly state they use Compur #0 & #1 S shutters but in the price list call them 0 & 1 shutters with self releases. Schneider call them Compur 0S & 1S. In the Photonet page for the Radionar you linked to the Self release can be seen as with your own lens.
Ian
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