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 Stir shield for Arduino Nano from Jens Warkentin.
 
 <p align="center">
-<img src="https://github.com/micworg/stir/blob/master/nanoshield/images/top.jpg" width=200>
-<img src="https://github.com/micworg/stir/blob/master/nanoshield/images/bottom.jpg" width=200>
+<img src="https://github.com/micworg/stir/blob/master/nanoshield/images/top.png" width=200>
+<img src="https://github.com/micworg/stir/blob/master/nanoshield/images/bottom.png" width=200>
 </p>
 
 
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