I have moved your thread to the Orders and Decorations Forum where you will get more attention
LIFE'S LOSERS NEVER LEARN FROM THE ERROR OF THEIR WAYS.
very nice badge I like it.
it looks like a nice original Deutsches Rote Kreuze Wasserrettungsdienst badge.
Here is one for sale:
Large WW2 German Red Cross Water Rescue Service Badge Large WW2 German Red Cross Water Rescue Service Badge [FC-SM113-22] - $185.00 : Soldiers Museum:, Buy/Sell/Trade Historical Militaria
and another here:
Hermann Historica - Internationales Auktionshaus für Antiken, Alte Waffen, Orden und Ehrenzeichen, Historische Sammlungsstücke
I would imagine it is just a proficiency badge that was awarded with pretty much the same qualifications to get the DLRG badge
All the best