diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index f605f8af..1b932fb5 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -1,3 +1,8 @@
+# 2.5.1
+
+* Fixed - py.typed file wasn't installed properly via setuptools.
+* Added type hints for the OpaqueKeyField subclasses (requires mypy plugin)
+
 # 2.5.0
 
 * Added python type hints
diff --git a/MANIFEST.in b/MANIFEST.in
index d75a27df..86cebd6c 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -6,4 +6,4 @@ include requirements/django.in
 recursive-include opaque_keys *.html *.png *.gif *js *.css *jpg *jpeg *svg *py
 include requirements/constraints.txt
 include requirements/base.txt
-
+include opaque_keys/py.typed
diff --git a/opaque_keys/__init__.py b/opaque_keys/__init__.py
index 64e88a4e..1b7fec68 100644
--- a/opaque_keys/__init__.py
+++ b/opaque_keys/__init__.py
@@ -14,7 +14,7 @@
 from stevedore.enabled import EnabledExtensionManager
 from typing_extensions import Self  # For python 3.11 plus, can just use "from typing import Self"
 
-__version__ = '2.5.0'
+__version__ = '2.5.1'
 
 
 class InvalidKeyError(Exception):
diff --git a/opaque_keys/edx/django/models.py b/opaque_keys/edx/django/models.py
index 4effd974..d9ed7372 100644
--- a/opaque_keys/edx/django/models.py
+++ b/opaque_keys/edx/django/models.py
@@ -194,6 +194,12 @@ class LearningContextKeyField(OpaqueKeyField):
     """
     description = "A LearningContextKey object, saved to the DB in the form of a string"
     KEY_CLASS = LearningContextKey
+    # Declare the field types for the django-stubs mypy type hint plugin.
+    # See https://github.com/typeddjango/django-stubs/blob/6a850f6/django-stubs/db/models/fields/__init__.pyi#L503-L511
+    # for examples of how this works for the standard field types in the upstream codebase.
+    # Note that these particular type annotations have no effect at runtime nor on Django itself nor on PyLance.
+    _pyi_private_set_type: LearningContextKey | str | None  # The types that you can set into this field.
+    _pyi_private_get_type: LearningContextKey | None  # The type that you get when you read from this field
 
 
 class CourseKeyField(OpaqueKeyField):
@@ -202,6 +208,9 @@ class CourseKeyField(OpaqueKeyField):
     """
     description = "A CourseKey object, saved to the DB in the form of a string"
     KEY_CLASS = CourseKey
+    # Declare the field types for the django-stubs mypy type hint plugin:
+    _pyi_private_set_type: CourseKey | str | None
+    _pyi_private_get_type: CourseKey | None
 
 
 class UsageKeyField(OpaqueKeyField):
@@ -210,6 +219,9 @@ class UsageKeyField(OpaqueKeyField):
     """
     description = "A Location object, saved to the DB in the form of a string"
     KEY_CLASS = UsageKey
+    # Declare the field types for the django-stubs mypy type hint plugin:
+    _pyi_private_set_type: UsageKey | str | None
+    _pyi_private_get_type: UsageKey | None
 
 
 class LocationKeyField(UsageKeyField):
@@ -228,3 +240,6 @@ class BlockTypeKeyField(OpaqueKeyField):
     """
     description = "A BlockTypeKey object, saved to the DB in the form of a string."
     KEY_CLASS = BlockTypeKey
+    # Declare the field types for the django-stubs mypy type hint plugin:
+    _pyi_private_set_type: BlockTypeKey | str | None
+    _pyi_private_get_type: BlockTypeKey | None