diff --git a/cscripts/cta_root2caldb.py b/cscripts/cta_root2caldb.py
index 93c7725..aa2a6d7 100755
--- a/cscripts/cta_root2caldb.py
+++ b/cscripts/cta_root2caldb.py
@@ -1383,7 +1383,7 @@ class caldb():
                                   self.bgd_bounds, self.bgd_desc)
 
             # BGD (reconstructed energy)
-            self.make_3D(array, self.hdu_bgd, "BGD", "1/s/MeV/sr", scale=bgdscale)
+            self.make_3D(array, self.hdu_bgd, "BGD", "MeV^-1 s^-1 sr^-1", scale=bgdscale)
 
         # Return
         return