diff --git a/pymongo/__init__.py b/pymongo/__init__.py
index 8116788bc3..6416f939e8 100644
--- a/pymongo/__init__.py
+++ b/pymongo/__init__.py
@@ -88,7 +88,7 @@
 
 from pymongo import _csot
 from pymongo._version import __version__, get_version_string, version_tuple
-from pymongo.common import MAX_SUPPORTED_WIRE_VERSION, MIN_SUPPORTED_WIRE_VERSION
+from pymongo.common import MAX_SUPPORTED_WIRE_VERSION, MIN_SUPPORTED_WIRE_VERSION, has_c
 from pymongo.cursor import CursorType
 from pymongo.operations import (
     DeleteMany,
@@ -116,16 +116,6 @@
 """Current version of PyMongo."""
 
 
-def has_c() -> bool:
-    """Is the C extension installed?"""
-    try:
-        from pymongo import _cmessage  # type: ignore[attr-defined] # noqa: F401
-
-        return True
-    except ImportError:
-        return False
-
-
 def timeout(seconds: Optional[float]) -> ContextManager[None]:
     """**(Provisional)** Apply the given timeout for a block of operations.
 
diff --git a/pymongo/common.py b/pymongo/common.py
index a073eba577..360389c25d 100644
--- a/pymongo/common.py
+++ b/pymongo/common.py
@@ -1060,3 +1060,13 @@ def update(self, other: Mapping[str, Any]) -> None:  # type: ignore[override]
 
     def cased_key(self, key: str) -> Any:
         return self.__casedkeys[key.lower()]
+
+
+def has_c() -> bool:
+    """Is the C extension installed?"""
+    try:
+        from pymongo import _cmessage  # type: ignore[attr-defined] # noqa: F401
+
+        return True
+    except ImportError:
+        return False
diff --git a/pymongo/pool_options.py b/pymongo/pool_options.py
index 6ec97d7d1b..61486c91c6 100644
--- a/pymongo/pool_options.py
+++ b/pymongo/pool_options.py
@@ -33,6 +33,7 @@
     MAX_POOL_SIZE,
     MIN_POOL_SIZE,
     WAIT_QUEUE_TIMEOUT,
+    has_c,
 )
 
 if TYPE_CHECKING:
@@ -363,6 +364,11 @@ def __init__(
         #    },
         #    'platform': 'CPython 3.8.0|MyPlatform'
         # }
+        if has_c():
+            self.__metadata["driver"]["name"] = "{}|{}".format(
+                self.__metadata["driver"]["name"],
+                "c",
+            )
         if not is_sync:
             self.__metadata["driver"]["name"] = "{}|{}".format(
                 self.__metadata["driver"]["name"],
diff --git a/test/asynchronous/test_client.py b/test/asynchronous/test_client.py
index f610f32779..7e4abc3cf1 100644
--- a/test/asynchronous/test_client.py
+++ b/test/asynchronous/test_client.py
@@ -95,7 +95,7 @@
 from pymongo.asynchronous.settings import TOPOLOGY_TYPE
 from pymongo.asynchronous.topology import _ErrorContext
 from pymongo.client_options import ClientOptions
-from pymongo.common import _UUID_REPRESENTATIONS, CONNECT_TIMEOUT
+from pymongo.common import _UUID_REPRESENTATIONS, CONNECT_TIMEOUT, has_c
 from pymongo.compression_support import _have_snappy, _have_zstd
 from pymongo.driver_info import DriverInfo
 from pymongo.errors import (
@@ -343,7 +343,10 @@ async def test_read_preference(self):
 
     async def test_metadata(self):
         metadata = copy.deepcopy(_METADATA)
-        metadata["driver"]["name"] = "PyMongo|async"
+        if has_c():
+            metadata["driver"]["name"] = "PyMongo|c|async"
+        else:
+            metadata["driver"]["name"] = "PyMongo|async"
         metadata["application"] = {"name": "foobar"}
         client = self.simple_client("mongodb://foo:27017/?appname=foobar&connect=false")
         options = client.options
@@ -366,7 +369,10 @@ async def test_metadata(self):
         with self.assertRaises(TypeError):
             self.simple_client(driver=("Foo", "1", "a"))
         # Test appending to driver info.
-        metadata["driver"]["name"] = "PyMongo|async|FooDriver"
+        if has_c():
+            metadata["driver"]["name"] = "PyMongo|c|async|FooDriver"
+        else:
+            metadata["driver"]["name"] = "PyMongo|async|FooDriver"
         metadata["driver"]["version"] = "{}|1.2.3".format(_METADATA["driver"]["version"])
         client = self.simple_client(
             "foo",
@@ -1927,7 +1933,10 @@ def test_sigstop_sigcont(self):
     async def _test_handshake(self, env_vars, expected_env):
         with patch.dict("os.environ", env_vars):
             metadata = copy.deepcopy(_METADATA)
-            metadata["driver"]["name"] = "PyMongo|async"
+            if has_c():
+                metadata["driver"]["name"] = "PyMongo|c|async"
+            else:
+                metadata["driver"]["name"] = "PyMongo|async"
             if expected_env is not None:
                 metadata["env"] = expected_env
 
diff --git a/test/test_client.py b/test/test_client.py
index bc45325f0b..47ff43e348 100644
--- a/test/test_client.py
+++ b/test/test_client.py
@@ -83,7 +83,7 @@
 from bson.tz_util import utc
 from pymongo import event_loggers, message, monitoring
 from pymongo.client_options import ClientOptions
-from pymongo.common import _UUID_REPRESENTATIONS, CONNECT_TIMEOUT
+from pymongo.common import _UUID_REPRESENTATIONS, CONNECT_TIMEOUT, has_c
 from pymongo.compression_support import _have_snappy, _have_zstd
 from pymongo.driver_info import DriverInfo
 from pymongo.errors import (
@@ -335,7 +335,10 @@ def test_read_preference(self):
 
     def test_metadata(self):
         metadata = copy.deepcopy(_METADATA)
-        metadata["driver"]["name"] = "PyMongo"
+        if has_c():
+            metadata["driver"]["name"] = "PyMongo|c"
+        else:
+            metadata["driver"]["name"] = "PyMongo"
         metadata["application"] = {"name": "foobar"}
         client = self.simple_client("mongodb://foo:27017/?appname=foobar&connect=false")
         options = client.options
@@ -358,7 +361,10 @@ def test_metadata(self):
         with self.assertRaises(TypeError):
             self.simple_client(driver=("Foo", "1", "a"))
         # Test appending to driver info.
-        metadata["driver"]["name"] = "PyMongo|FooDriver"
+        if has_c():
+            metadata["driver"]["name"] = "PyMongo|c|FooDriver"
+        else:
+            metadata["driver"]["name"] = "PyMongo|FooDriver"
         metadata["driver"]["version"] = "{}|1.2.3".format(_METADATA["driver"]["version"])
         client = self.simple_client(
             "foo",
@@ -1885,7 +1891,10 @@ def test_sigstop_sigcont(self):
     def _test_handshake(self, env_vars, expected_env):
         with patch.dict("os.environ", env_vars):
             metadata = copy.deepcopy(_METADATA)
-            metadata["driver"]["name"] = "PyMongo"
+            if has_c():
+                metadata["driver"]["name"] = "PyMongo|c"
+            else:
+                metadata["driver"]["name"] = "PyMongo"
             if expected_env is not None:
                 metadata["env"] = expected_env
 
diff --git a/tools/synchro.py b/tools/synchro.py
index 59d6e653e5..77166dd84c 100644
--- a/tools/synchro.py
+++ b/tools/synchro.py
@@ -101,6 +101,7 @@
     "default_async": "default",
     "aclose": "close",
     "PyMongo|async": "PyMongo",
+    "PyMongo|c|async": "PyMongo|c",
     "AsyncTestGridFile": "TestGridFile",
     "AsyncTestGridFileNoConnect": "TestGridFileNoConnect",
 }