diff --git a/nipype/interfaces/afni/tests/test_auto_CatMatvec.py b/nipype/interfaces/afni/tests/test_auto_CatMatvec.py
index dc1c981bb3..df0ac34e09 100644
--- a/nipype/interfaces/afni/tests/test_auto_CatMatvec.py
+++ b/nipype/interfaces/afni/tests/test_auto_CatMatvec.py
@@ -38,7 +38,10 @@ def test_CatMatvec_inputs():
         ),
         out_file=dict(
             argstr=' > %s',
+            keep_extension=False,
             mandatory=True,
+            name_source='in_file',
+            name_template='%s_cat.aff12.1D',
             position=-1,
         ),
         outputtype=dict(),
diff --git a/nipype/interfaces/afni/utils.py b/nipype/interfaces/afni/utils.py
index 9f306c7b85..cb01ae4a2b 100644
--- a/nipype/interfaces/afni/utils.py
+++ b/nipype/interfaces/afni/utils.py
@@ -564,8 +564,11 @@ class CatMatvecInputSpec(AFNICommandInputSpec):
         argstr="%s",
         position=-2)
     out_file = File(
-        desc="File to write concattenated matvecs to",
         argstr=" > %s",
+        name_template='%s_cat.aff12.1D',
+        name_source='in_file',
+        keep_extension=False,
+        desc="File to write concattenated matvecs to",
         position=-1,
         mandatory=True)
     matrix = traits.Bool(