diff --git a/quantumclient/quantum/v2_0/extension.py b/quantumclient/quantum/v2_0/extension.py
index df4a88b..1ebea6f 100644
--- a/quantumclient/quantum/v2_0/extension.py
+++ b/quantumclient/quantum/v2_0/extension.py
@@ -17,79 +17,28 @@
 
 import logging
 
-from cliff import lister
-from cliff import show
-
-from quantumclient.common import utils
-from quantumclient.quantum.v2_0 import QuantumCommand
+from quantumclient.quantum import v2_0 as cmd_base
 
 
-class ListExt(QuantumCommand, lister.Lister):
-    """List all exts."""
+class ListExt(cmd_base.ListCommand):
+    """List all extensions."""
 
-    api = 'network'
     resource = 'extension'
     log = logging.getLogger(__name__ + '.ListExt')
-    _formatters = None
-
-    def get_parser(self, prog_name):
-        parser = super(ListExt, self).get_parser(prog_name)
-        return parser
-
-    def get_data(self, parsed_args):
-        self.log.debug('get_data(%s)' % parsed_args)
-        quantum_client = self.get_client()
-        search_opts = {}
-        quantum_client.format = parsed_args.request_format
-        obj_lister = getattr(quantum_client,
-                             "list_%ss" % self.resource)
-        data = obj_lister(**search_opts)
-        info = []
-        collection = self.resource + "s"
-        if collection in data:
-            info = data[collection]
-        _columns = len(info) > 0 and sorted(info[0].keys()) or []
-        return (_columns, (utils.get_item_properties(s, _columns)
-                for s in info))
+    list_columns = ['alias', 'name']
 
 
-class ShowExt(QuantumCommand, show.ShowOne):
-    """Show information of a given resource
+class ShowExt(cmd_base.ShowCommand):
+    """Show information of a given resource."""
 
-    """
-    api = 'network'
     resource = "extension"
     log = logging.getLogger(__name__ + '.ShowExt')
+    allow_names = False
 
     def get_parser(self, prog_name):
-        parser = super(ShowExt, self).get_parser(prog_name)
+        parser = super(cmd_base.ShowCommand, self).get_parser(prog_name)
+        cmd_base.add_show_list_common_argument(parser)
         parser.add_argument(
-            'ext_alias', metavar='ext-alias',
+            'id', metavar='EXT-ALIAS',
             help='the extension alias')
         return parser
-
-    def get_data(self, parsed_args):
-        self.log.debug('get_data(%s)' % parsed_args)
-        quantum_client = self.get_client()
-        quantum_client.format = parsed_args.request_format
-        params = {}
-        obj_shower = getattr(quantum_client,
-                             "show_%s" % self.resource)
-        data = obj_shower(parsed_args.ext_alias, **params)
-        if self.resource in data:
-            for k, v in data[self.resource].iteritems():
-                if isinstance(v, list):
-                    value = ""
-                    for _item in v:
-                        if value:
-                            value += "\n"
-                        if isinstance(_item, dict):
-                            value += utils.dumps(_item)
-                        else:
-                            value += str(_item)
-                    data[self.resource][k] = value
-                elif v is None:
-                    data[self.resource][k] = ''
-            return zip(*sorted(data[self.resource].iteritems()))
-        else:
-            return None
diff --git a/quantumclient/quantum/v2_0/floatingip.py b/quantumclient/quantum/v2_0/floatingip.py
index 3916527..3a4982a 100644
--- a/quantumclient/quantum/v2_0/floatingip.py
+++ b/quantumclient/quantum/v2_0/floatingip.py
@@ -31,7 +31,6 @@ class ListFloatingIP(ListCommand):
 
     resource = 'floatingip'
     log = logging.getLogger(__name__ + '.ListFloatingIP')
-    _formatters = {}
     list_columns = ['id', 'fixed_ip_address', 'floating_ip_address',
                     'port_id']
     pagination_support = True
diff --git a/quantumclient/quantum/v2_0/lb/healthmonitor.py b/quantumclient/quantum/v2_0/lb/healthmonitor.py
index a4e7ee6..3ecdd56 100644
--- a/quantumclient/quantum/v2_0/lb/healthmonitor.py
+++ b/quantumclient/quantum/v2_0/lb/healthmonitor.py
@@ -28,7 +28,6 @@ class ListHealthMonitor(quantumv20.ListCommand):
     resource = 'health_monitor'
     log = logging.getLogger(__name__ + '.ListHealthMonitor')
     list_columns = ['id', 'type', 'admin_state_up', 'status']
-    _formatters = {}
     pagination_support = True
     sorting_support = True
 
diff --git a/quantumclient/quantum/v2_0/lb/member.py b/quantumclient/quantum/v2_0/lb/member.py
index 18e479a..05fb430 100644
--- a/quantumclient/quantum/v2_0/lb/member.py
+++ b/quantumclient/quantum/v2_0/lb/member.py
@@ -30,7 +30,6 @@ class ListMember(quantumv20.ListCommand):
     list_columns = [
         'id', 'address', 'protocol_port', 'admin_state_up', 'status'
     ]
-    _formatters = {}
     pagination_support = True
     sorting_support = True
 
diff --git a/quantumclient/quantum/v2_0/lb/pool.py b/quantumclient/quantum/v2_0/lb/pool.py
index 26bf0c9..3d1d580 100644
--- a/quantumclient/quantum/v2_0/lb/pool.py
+++ b/quantumclient/quantum/v2_0/lb/pool.py
@@ -29,7 +29,6 @@ class ListPool(quantumv20.ListCommand):
     log = logging.getLogger(__name__ + '.ListPool')
     list_columns = ['id', 'name', 'lb_method', 'protocol',
                     'admin_state_up', 'status']
-    _formatters = {}
     pagination_support = True
     sorting_support = True
 
diff --git a/quantumclient/quantum/v2_0/lb/vip.py b/quantumclient/quantum/v2_0/lb/vip.py
index 4ee03a1..c3795c3 100644
--- a/quantumclient/quantum/v2_0/lb/vip.py
+++ b/quantumclient/quantum/v2_0/lb/vip.py
@@ -29,7 +29,6 @@ class ListVip(quantumv20.ListCommand):
     log = logging.getLogger(__name__ + '.ListVip')
     list_columns = ['id', 'name', 'algorithm', 'address', 'protocol',
                     'admin_state_up', 'status']
-    _formatters = {}
     pagination_support = True
     sorting_support = True
 
diff --git a/quantumclient/quantum/v2_0/nvp_qos_queue.py b/quantumclient/quantum/v2_0/nvp_qos_queue.py
index 040ce16..386b887 100644
--- a/quantumclient/quantum/v2_0/nvp_qos_queue.py
+++ b/quantumclient/quantum/v2_0/nvp_qos_queue.py
@@ -25,7 +25,6 @@ class ListQoSQueue(quantumv20.ListCommand):
 
     resource = 'qos_queue'
     log = logging.getLogger(__name__ + '.ListQoSQueue')
-    _formatters = {}
     list_columns = ['id', 'name', 'min', 'max',
                     'qos_marking', 'dscp', 'default']
 
diff --git a/quantumclient/quantum/v2_0/nvpnetworkgateway.py b/quantumclient/quantum/v2_0/nvpnetworkgateway.py
index 2c668ac..72a83b3 100644
--- a/quantumclient/quantum/v2_0/nvpnetworkgateway.py
+++ b/quantumclient/quantum/v2_0/nvpnetworkgateway.py
@@ -27,7 +27,6 @@ class ListNetworkGateway(quantumv20.ListCommand):
     """List network gateways for a given tenant."""
 
     resource = RESOURCE
-    _formatters = {}
     log = logging.getLogger(__name__ + '.ListNetworkGateway')
     list_columns = ['id', 'name']
 
diff --git a/quantumclient/quantum/v2_0/quota.py b/quantumclient/quantum/v2_0/quota.py
index bdff0bd..2b1752f 100644
--- a/quantumclient/quantum/v2_0/quota.py
+++ b/quantumclient/quantum/v2_0/quota.py
@@ -70,7 +70,6 @@ class ListQuota(QuantumCommand, lister.Lister):
     api = 'network'
     resource = 'quota'
     log = logging.getLogger(__name__ + '.ListQuota')
-    _formatters = None
 
     def get_parser(self, prog_name):
         parser = super(ListQuota, self).get_parser(prog_name)
diff --git a/quantumclient/quantum/v2_0/securitygroup.py b/quantumclient/quantum/v2_0/securitygroup.py
index c66d012..5fa899c 100644
--- a/quantumclient/quantum/v2_0/securitygroup.py
+++ b/quantumclient/quantum/v2_0/securitygroup.py
@@ -26,7 +26,6 @@ class ListSecurityGroup(quantumv20.ListCommand):
 
     resource = 'security_group'
     log = logging.getLogger(__name__ + '.ListSecurityGroup')
-    _formatters = {}
     list_columns = ['id', 'name', 'description']
     pagination_support = True
     sorting_support = True
@@ -103,7 +102,6 @@ class ListSecurityGroupRule(quantumv20.ListCommand):
 
     resource = 'security_group_rule'
     log = logging.getLogger(__name__ + '.ListSecurityGroupRule')
-    _formatters = {}
     list_columns = ['id', 'security_group_id', 'direction', 'protocol',
                     'remote_ip_prefix', 'remote_group_id']
     replace_rules = {'security_group_id': 'security_group',
diff --git a/quantumclient/v2_0/client.py b/quantumclient/v2_0/client.py
index fb55b1e..e4982b4 100644
--- a/quantumclient/v2_0/client.py
+++ b/quantumclient/v2_0/client.py
@@ -153,8 +153,8 @@ class Client(object):
     subnet_path = "/subnets/%s"
     quotas_path = "/quotas"
     quota_path = "/quotas/%s"
-    exts_path = "/extensions"
-    ext_path = "/extensions/%s"
+    extensions_path = "/extensions"
+    extension_path = "/extensions/%s"
     routers_path = "/routers"
     router_path = "/routers/%s"
     floatingips_path = "/floatingips"
@@ -245,12 +245,12 @@ class Client(object):
     @APIParamsCall
     def list_extensions(self, **_params):
         """Fetch a list of all exts on server side."""
-        return self.get(self.exts_path, params=_params)
+        return self.get(self.extensions_path, params=_params)
 
     @APIParamsCall
     def show_extension(self, ext_alias, **_params):
         """Fetch a list of all exts on server side."""
-        return self.get(self.ext_path % ext_alias, params=_params)
+        return self.get(self.extension_path % ext_alias, params=_params)
 
     @APIParamsCall
     def list_ports(self, retrieve_all=True, **_params):
diff --git a/tests/unit/test_cli20.py b/tests/unit/test_cli20.py
index 9370295..aed7487 100644
--- a/tests/unit/test_cli20.py
+++ b/tests/unit/test_cli20.py
@@ -145,6 +145,7 @@ class CLITestV20Base(testtools.TestCase):
 
     format = 'json'
     test_id = 'aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa'
+    id_field = 'id'
 
     def _find_resourceid(self, client, resource, name_or_id):
         return name_or_id
@@ -206,7 +207,7 @@ class CLITestV20Base(testtools.TestCase):
         for i in xrange(len(position_names)):
             body[resource].update({position_names[i]: position_values[i]})
         ress = {resource:
-                {'id': myid}, }
+                {self.id_field: myid}, }
         if name:
             ress[resource].update({'name': name})
         self.client.format = self.format
@@ -253,12 +254,16 @@ class CLITestV20Base(testtools.TestCase):
 
     def _test_list_resources(self, resources, cmd, detail=False, tags=[],
                              fields_1=[], fields_2=[], page_size=None,
-                             sort_key=[], sort_dir=[]):
+                             sort_key=[], sort_dir=[], response_contents=None):
         self.mox.StubOutWithMock(cmd, "get_client")
         self.mox.StubOutWithMock(self.client.httpclient, "request")
         cmd.get_client().MultipleTimes().AndReturn(self.client)
-        reses = {resources: [{'id': 'myid1', },
-                             {'id': 'myid2', }, ], }
+        if response_contents is None:
+            contents = [{self.id_field: 'myid1', },
+                        {self.id_field: 'myid2', }, ]
+        else:
+            contents = response_contents
+        reses = {resources: contents}
         self.client.format = self.format
         resstr = self.client.serialize(reses)
         # url method body
@@ -335,7 +340,9 @@ class CLITestV20Base(testtools.TestCase):
         self.mox.VerifyAll()
         self.mox.UnsetStubs()
         _str = self.fake_stdout.make_string()
-        self.assertTrue('myid1' in _str)
+        if response_contents is None:
+            self.assertTrue('myid1' in _str)
+        return _str
 
     def _test_list_resources_with_pagination(self, resources, cmd):
         self.mox.StubOutWithMock(cmd, "get_client")
@@ -399,8 +406,8 @@ class CLITestV20Base(testtools.TestCase):
         cmd.get_client().MultipleTimes().AndReturn(self.client)
         query = "&".join(["fields=%s" % field for field in fields])
         expected_res = {resource:
-                        {'id': myid,
-                        'name': 'myname', }, }
+                        {self.id_field: myid,
+                         'name': 'myname', }, }
         self.client.format = self.format
         resstr = self.client.serialize(expected_res)
         path = getattr(self.client, resource + "_path")
diff --git a/tests/unit/test_cli20_extensions.py b/tests/unit/test_cli20_extensions.py
new file mode 100644
index 0000000..874de77
--- /dev/null
+++ b/tests/unit/test_cli20_extensions.py
@@ -0,0 +1,49 @@
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright 2013 NEC Corporation
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+import sys
+
+from quantumclient.quantum.v2_0.extension import ListExt
+from quantumclient.quantum.v2_0.extension import ShowExt
+from tests.unit.test_cli20 import CLITestV20Base
+from tests.unit.test_cli20 import MyApp
+
+
+class CLITestV20Extension(CLITestV20Base):
+    id_field = 'alias'
+
+    def test_list_extensions(self):
+        resources = 'extensions'
+        cmd = ListExt(MyApp(sys.stdout), None)
+        contents = [{'alias': 'ext1', 'name': 'name1', 'other': 'other1'},
+                    {'alias': 'ext2', 'name': 'name2', 'other': 'other2'}]
+        ret = self._test_list_resources(resources, cmd,
+                                        response_contents=contents)
+        ret_words = set(ret.split())
+        # Check only the default columns are shown.
+        self.assertTrue('name' in ret_words)
+        self.assertTrue('alias' in ret_words)
+        self.assertFalse('other' in ret_words)
+
+    def test_show_extension(self):
+        # -F option does not work for ext-show at the moment, so -F option
+        # is not passed in the commandline args as other tests do.
+        resource = 'extension'
+        cmd = ShowExt(MyApp(sys.stdout), None)
+        args = [self.test_id]
+        ext_alias = self.test_id
+        self._test_show_resource(resource, cmd, ext_alias, args, fields=[])