diff --git a/boundaries/boundaryhandling.py b/boundaries/boundaryhandling.py
index 0c72ab34b89065fe3ff36694a0c1e37212715d7a..dea8267688c115eceeb0082044c2f60524d04d7e 100644
--- a/boundaries/boundaryhandling.py
+++ b/boundaries/boundaryhandling.py
@@ -318,7 +318,7 @@ class BoundaryHandling:
         def to_cpu(gpu_version, cpu_version):
             gpu_version = gpu_version.boundary_object_to_index_list
             cpu_version = cpu_version.boundary_object_to_index_list
-            for obj, cpu_arr in cpu_version.values():
+            for obj, cpu_arr in cpu_version.items():
                 gpu_version[obj].get(cpu_arr)
 
         @staticmethod