diff --git a/nipype/interfaces/ants/tests/test_auto_AffineInitializer.py b/nipype/interfaces/ants/tests/test_auto_AffineInitializer.py
index 2c1f05f864..319798e13f 100644
--- a/nipype/interfaces/ants/tests/test_auto_AffineInitializer.py
+++ b/nipype/interfaces/ants/tests/test_auto_AffineInitializer.py
@@ -28,6 +28,9 @@ def test_AffineInitializer_inputs():
     mandatory=True,
     position=2,
     ),
+    num_threads=dict(nohash=True,
+    usedefault=True,
+    ),
     out_file=dict(argstr='%s',
     position=3,
     usedefault=True,
diff --git a/nipype/interfaces/ants/utils.py b/nipype/interfaces/ants/utils.py
index db287e6b68..d356f727dd 100644
--- a/nipype/interfaces/ants/utils.py
+++ b/nipype/interfaces/ants/utils.py
@@ -181,7 +181,7 @@ def _list_outputs(self):
         return outputs
 
 
-class AffineInitializerInputSpec(CommandLineInputSpec):
+class AffineInitializerInputSpec(ANTSCommandInputSpec):
     dimension = traits.Enum(3, 2, usedefault=True, position=0, argstr='%s',
                             desc='dimension')
     fixed_image = File(exists=True, mandatory=True, position=1, argstr='%s',
@@ -207,7 +207,7 @@ class AffineInitializerOutputSpec(TraitedSpec):
     out_file = File(desc='output transform file')
 
 
-class AffineInitializer(CommandLine):
+class AffineInitializer(ANTSCommand):
     """
     Initialize an affine transform (as in antsBrainExtraction.sh)