diff --git a/sarsen/sentinel1.py b/sarsen/sentinel1.py
index 538e407..208d5ce 100644
--- a/sarsen/sentinel1.py
+++ b/sarsen/sentinel1.py
@@ -201,7 +201,7 @@ def product_info(self, **kwargs: Any) -> Dict[str, Any]:
         """Get information about the Sentinel-1 product."""
         measurement_groups = self.all_measurement_groups()
 
-        self.measurement_group = measurement_groups[0]
+        self.measurement_group = self.measurement_group or measurement_groups[0]
         gcp = self.gcp
 
         bbox = [