diff --git a/tge/outputters/pickle.py b/tge/outputters/pickle.py
index cf9d5c1..92e37f4 100644
--- a/tge/outputters/pickle.py
+++ b/tge/outputters/pickle.py
@@ -1,5 +1,5 @@
 import pickle
 
 def output (data, destination):
-    with open(destination, "w") as out_file:
+    with open(destination, "wb") as out_file:
         pickle.dump(data, out_file)