diff --git a/src/vws/transports.py b/src/vws/transports.py
index 80aa989f..5dd9db23 100644
--- a/src/vws/transports.py
+++ b/src/vws/transports.py
@@ -1,7 +1,7 @@
 """HTTP transport implementations for VWS clients."""
 
 from collections.abc import Awaitable
-from typing import Protocol, Self, runtime_checkable
+from typing import Protocol, Self, assert_never, runtime_checkable
 
 import httpx
 import requests
@@ -10,6 +10,30 @@
 from vws.response import Response
 
 
+@beartype(conf=BeartypeConf(is_pep484_tower=True))
+def _httpx_timeout(
+    request_timeout: float | tuple[float, float],
+) -> httpx.Timeout:
+    """Build an ``httpx.Timeout`` from a request timeout value."""
+    match request_timeout:
+        case (connect, read):
+            return httpx.Timeout(
+                connect=connect,
+                read=read,
+                write=None,
+                pool=None,
+            )
+        case float() | int() as timeout:
+            return httpx.Timeout(
+                connect=timeout,
+                read=timeout,
+                write=None,
+                pool=None,
+            )
+        case _ as unreachable:
+            assert_never(unreachable)  # pyrefly: ignore[bad-argument-type]  # ty: ignore[type-assertion-failure]
+
+
 @runtime_checkable
 class Transport(Protocol):
     """Protocol for HTTP transports used by VWS clients.
@@ -149,21 +173,7 @@ def __call__(
         Returns:
             A Response populated from the httpx response.
         """
-        if isinstance(request_timeout, tuple):
-            connect_timeout, read_timeout = request_timeout
-            httpx_timeout = httpx.Timeout(
-                connect=connect_timeout,
-                read=read_timeout,
-                write=None,
-                pool=None,
-            )
-        else:
-            httpx_timeout = httpx.Timeout(
-                connect=request_timeout,
-                read=request_timeout,
-                write=None,
-                pool=None,
-            )
+        httpx_timeout = _httpx_timeout(request_timeout=request_timeout)
 
         httpx_response = self._client.request(
             method=method,
@@ -272,21 +282,7 @@ async def __call__(
         Returns:
             A Response populated from the httpx response.
         """
-        if isinstance(request_timeout, tuple):
-            connect_timeout, read_timeout = request_timeout
-            httpx_timeout = httpx.Timeout(
-                connect=connect_timeout,
-                read=read_timeout,
-                write=None,
-                pool=None,
-            )
-        else:
-            httpx_timeout = httpx.Timeout(
-                connect=request_timeout,
-                read=request_timeout,
-                write=None,
-                pool=None,
-            )
+        httpx_timeout = _httpx_timeout(request_timeout=request_timeout)
 
         httpx_response = await self._client.request(
             method=method,