diff --git a/arm/arm/launch_utils.py b/arm/arm/launch_utils.py
index cf947ca..03eddfc 100644
--- a/arm/arm/launch_utils.py
+++ b/arm/arm/launch_utils.py
@@ -45,7 +45,7 @@ def create_replay(batch_size: int, timesteps: int, prioritisation: bool,
         reward_dtype=np.float32,
         update_horizon=1,
         observation_elements=observation_elements,
-        extra_replay_elements=[ReplayElement('demo', (), np.bool)]
+        extra_replay_elements=[ReplayElement('demo', (), bool)]
     )
     return replay_buffer