diff --git a/git/cmd.py b/git/cmd.py
index 54537a41d..da69241e7 100644
--- a/git/cmd.py
+++ b/git/cmd.py
@@ -885,7 +885,7 @@ def transform_kwarg(self, name, value, split_single_char_options):
         if len(name) == 1:
             if value is True:
                 return ["-%s" % name]
-            elif type(value) is not bool:
+            elif value not in (False, None):
                 if split_single_char_options:
                     return ["-%s" % name, "%s" % value]
                 else:
@@ -893,7 +893,7 @@ def transform_kwarg(self, name, value, split_single_char_options):
         else:
             if value is True:
                 return ["--%s" % dashify(name)]
-            elif type(value) is not bool:
+            elif value not in (False, None):
                 return ["--%s=%s" % (dashify(name), value)]
         return []
 
diff --git a/git/test/test_git.py b/git/test/test_git.py
index c6180f7c9..60d3d53c3 100644
--- a/git/test/test_git.py
+++ b/git/test/test_git.py
@@ -81,13 +81,15 @@ def test_it_raises_errors(self):
     def test_it_transforms_kwargs_into_git_command_arguments(self):
         assert_equal(["-s"], self.git.transform_kwargs(**{'s': True}))
         assert_equal(["-s", "5"], self.git.transform_kwargs(**{'s': 5}))
+        assert_equal([], self.git.transform_kwargs(**{'s': None}))
 
         assert_equal(["--max-count"], self.git.transform_kwargs(**{'max_count': True}))
         assert_equal(["--max-count=5"], self.git.transform_kwargs(**{'max_count': 5}))
+        assert_equal([], self.git.transform_kwargs(**{'max_count': None}))
 
         # Multiple args are supported by using lists/tuples
         assert_equal(["-L", "1-3", "-L", "12-18"], self.git.transform_kwargs(**{'L': ('1-3', '12-18')}))
-        assert_equal(["-C", "-C"], self.git.transform_kwargs(**{'C': [True, True]}))
+        assert_equal(["-C", "-C"], self.git.transform_kwargs(**{'C': [True, True, None, False]}))
 
         # order is undefined
         res = self.git.transform_kwargs(**{'s': True, 't': True})