The district Sächsische Schweiz uses the name of its main town , Pirna , in its code PIR , to avoid the use of SS , the name of the paramilitary organization ; similarly SA is also unused .
The district Sächsische Schweiz uses the name of its main town , Pirna , in its code PIR , to avoid the use of SS , the name of the nazi group ; similarly SA is also unused .