diff --git a/reciprocalspaceship/io/crystfel.py b/reciprocalspaceship/io/crystfel.py
index 3729cac6..080d4c90 100644
--- a/reciprocalspaceship/io/crystfel.py
+++ b/reciprocalspaceship/io/crystfel.py
@@ -7,7 +7,7 @@
 import gemmi
 import numpy as np
 
-from reciprocalspaceship import DataSeries, DataSet, concat
+from reciprocalspaceship import DataSet, concat
 from reciprocalspaceship.utils import angle_between, eV2Angstroms
 
 # See Rupp Table 5-2