diff --git a/litellm/proxy/common_utils/callback_utils.py b/litellm/proxy/common_utils/callback_utils.py
index e718255750..d52592952b 100644
--- a/litellm/proxy/common_utils/callback_utils.py
+++ b/litellm/proxy/common_utils/callback_utils.py
@@ -317,17 +317,26 @@ def get_remaining_tokens_and_requests_from_request_data(data: Dict) -> Dict[str,
     _metadata = data.get("metadata", None) or {}
     model_group = get_model_group_from_request_data(data)
 
+    # The h11 package considers "/" or ":" invalid and raise a LocalProtocolError
+    h11_model_group_name = (
+        model_group.replace("/", "-").replace(":", "-") if model_group else None
+    )
+
     # Remaining Requests
     remaining_requests_variable_name = f"litellm-key-remaining-requests-{model_group}"
     remaining_requests = _metadata.get(remaining_requests_variable_name, None)
     if remaining_requests:
-        headers[f"x-litellm-key-remaining-requests-{model_group}"] = remaining_requests
+        headers[f"x-litellm-key-remaining-requests-{h11_model_group_name}"] = (
+            remaining_requests
+        )
 
     # Remaining Tokens
     remaining_tokens_variable_name = f"litellm-key-remaining-tokens-{model_group}"
     remaining_tokens = _metadata.get(remaining_tokens_variable_name, None)
     if remaining_tokens:
-        headers[f"x-litellm-key-remaining-tokens-{model_group}"] = remaining_tokens
+        headers[f"x-litellm-key-remaining-tokens-{h11_model_group_name}"] = (
+            remaining_tokens
+        )
 
     return headers
 
diff --git a/tests/test_litellm/proxy/common_utils/test_callback_utils.py b/tests/test_litellm/proxy/common_utils/test_callback_utils.py
new file mode 100644
index 0000000000..b9ed4b9b50
--- /dev/null
+++ b/tests/test_litellm/proxy/common_utils/test_callback_utils.py
@@ -0,0 +1,29 @@
+import sys
+import os
+
+sys.path.insert(
+    0, os.path.abspath("../../..")
+)  # Adds the parent directory to the system path
+
+from litellm.proxy.common_utils.callback_utils import (
+    get_remaining_tokens_and_requests_from_request_data,
+)
+
+
+def test_get_remaining_tokens_and_requests_from_request_data():
+    model_group = "openrouter/google/gemini-2.0-flash-001"
+    casedata = {
+        "metadata": {
+            "model_group": model_group,
+            f"litellm-key-remaining-requests-{model_group}": 100,
+            f"litellm-key-remaining-tokens-{model_group}": 200,
+        }
+    }
+
+    headers = get_remaining_tokens_and_requests_from_request_data(casedata)
+
+    expected_name = "openrouter-google-gemini-2.0-flash-001"
+    assert headers == {
+        f"x-litellm-key-remaining-requests-{expected_name}": 100,
+        f"x-litellm-key-remaining-tokens-{expected_name}": 200,
+    }