diff --git a/e3dc/_e3dc.py b/e3dc/_e3dc.py
index 5d3cfe4..f3cf714 100644
--- a/e3dc/_e3dc.py
+++ b/e3dc/_e3dc.py
@@ -137,7 +137,7 @@ def _set_serial(self, serial):
                 self.serialNumberPrefix = 'Q10-'
         elif self.serialNumber.startswith("7"):
             self.model = "Pro"
-            self.pmIndex = 0
+            self.pmIndex = 6
             self.pmIndexExt = 1
             if not self.serialNumberPrefix:
                 self.serialNumberPrefix = 'P10-'