diff --git a/tobiko/http/_session.py b/tobiko/http/_session.py
index 8447d2205..6319b6d80 100644
--- a/tobiko/http/_session.py
+++ b/tobiko/http/_session.py
@@ -42,7 +42,9 @@ def setup_http_session(session, ssh_client=None):
 
 # All known keyword arguments that could be provided to the pool manager, its
 # pools, or the underlying connections. This is used to construct a pool key.
-_key_fields = tuple(poolmanager._key_fields) + ('key_ssh_client',)
+_key_fields = tuple(
+    poolmanager._key_fields  # type: ignore
+) + ('key_ssh_client',)
 
 
 class PoolKey(collections.namedtuple("PoolKey", _key_fields)):  # type: ignore
@@ -57,10 +59,12 @@ class PoolKey(collections.namedtuple("PoolKey", _key_fields)):  # type: ignore
 #: Each PoolManager makes a copy of this dictionary so they can be configured
 #: globally here, or individually on the instance.
 key_fn_by_scheme = {
-    "http": functools.partial(poolmanager._default_key_normalizer,
-                              PoolKey),
-    "https": functools.partial(poolmanager._default_key_normalizer,
-                               PoolKey),
+    "http": functools.partial(
+        poolmanager._default_key_normalizer,  # type: ignore
+        PoolKey),
+    "https": functools.partial(
+        poolmanager._default_key_normalizer,  # type: ignore
+        PoolKey),
 }
 
 # pylint: enable=protected-access
diff --git a/tobiko/shell/ssh/_client.py b/tobiko/shell/ssh/_client.py
index fb07afbf9..39e8f78c4 100644
--- a/tobiko/shell/ssh/_client.py
+++ b/tobiko/shell/ssh/_client.py
@@ -578,13 +578,14 @@ def ssh_client(host, port=None, username=None, proxy_jump=None,
                               **connect_parameters)
 
 
-def load_private_keys(key_filenames: typing.List[str]):
-    pkeys = []
+def load_private_keys(key_filenames: typing.List[str]) \
+        -> typing.List[paramiko.PKey]:
+    pkeys: typing.List[paramiko.PKey] = []
     for filename in key_filenames:
         if os.path.exists(filename):
             try:
                 with io.open(filename, 'rt') as fd:
-                    pkey = paramiko.RSAKey.from_private_key(fd)
+                    pkey: paramiko.PKey = paramiko.RSAKey.from_private_key(fd)
             except Exception:
                 LOG.error('Unable to get RSAKey private key from file: '
                           f'{filename}', exc_info=1)