diff --git a/hironx_ros_bridge/src/hironx_ros_bridge/hironx_client.py b/hironx_ros_bridge/src/hironx_ros_bridge/hironx_client.py
index 33edfe2d..70d645b5 100644
--- a/hironx_ros_bridge/src/hironx_ros_bridge/hironx_client.py
+++ b/hironx_ros_bridge/src/hironx_ros_bridge/hironx_client.py
@@ -310,13 +310,25 @@ class via the link above; nicely formatted api doc web page
     # This shouldn't be accessed once turned to True during `init` method.
     is_rtc_activated = False
 
+    # Default set of RTCs to be activated.
     _RTC_list = [
             ['seq', "SequencePlayer"],
             ['sh', "StateHolder"],
             ['fk', "ForwardKinematics"],
             ['ic', "ImpedanceController"],
             ['el', "SoftErrorLimiter"],
-            # ['co', "CollisionDetector"],
+            ['sc', "ServoController"],
+            ['log', "DataLogger"],
+        ]
+
+    # All available RTCs. This list is meant to be immutable.
+    RTCs_all_available = [
+            ['seq', "SequencePlayer"],
+            ['sh', "StateHolder"],
+            ['fk', "ForwardKinematics"],
+            ['ic', "ImpedanceController"],
+            ['el', "SoftErrorLimiter"],
+            ['co', "CollisionDetector"],
             ['sc', "ServoController"],
             ['log', "DataLogger"],
         ]
@@ -491,8 +503,11 @@ def getRTCList(self, rtcs_str=None):
                 if not all(x in rtcs_req_list for x in self._RTC_NAME_MINREQ):
                     raise ValueError('{} are required at minimum'.format(
                         self._RTC_NAME_MINREQ))
+
+                # Create a new list of requested RTC with the name of
+                # implementations.
                 for rtc_requested in rtcs_req_list:
-                    for elem in self._RTC_list:
+                    for elem in self.RTCs_all_available:
                         if elem[0] == rtc_requested:
                             new_rtcs.append(elem)
                             break
diff --git a/hironx_ros_bridge/src/hironx_ros_bridge/testutil/test_hironx_client.py b/hironx_ros_bridge/test/test_hironx_client.py
similarity index 89%
rename from hironx_ros_bridge/src/hironx_ros_bridge/testutil/test_hironx_client.py
rename to hironx_ros_bridge/test/test_hironx_client.py
index 0106957e..49c923ab 100755
--- a/hironx_ros_bridge/src/hironx_ros_bridge/testutil/test_hironx_client.py
+++ b/hironx_ros_bridge/test/test_hironx_client.py
@@ -41,18 +41,6 @@
 
 class TestHiroClient(TestHiro):
 
-    _RTC_LIST = [
-            ['seq', "SequencePlayer"],
-            ['sh', "StateHolder"],
-            ['fk', "ForwardKinematics"],
-            ['ic', "ImpedanceController"],
-            ['el', "SoftErrorLimiter"],
-            ['sc', "ServoController"],
-            ['log', "DataLogger"],
-            # rmfo will be automatically added in getRTCList.
-            ['rmfo', 'RemoveForceSensorLinkOffset']
-        ]
-
     _RTC_LIST_CUSTOM = [
             ['seq', "SequencePlayer"],
             ['sh', "StateHolder"],
@@ -80,7 +68,9 @@ def test_getRTCList(self):
         '''
         self.assertTrue(
             self._compare_2dlist(
-                self.robot.getRTCList(), self._RTC_LIST))
+                self.robot.getRTCList(),
+                # Accessing a private member var only for testing purpose. 
+                self.robot._RTC_list))
 
     def test_getRTCList_customrtcs_args_correct(self):
         '''