diff --git a/model_utils/managers.py b/model_utils/managers.py
index d4a3450..c9ec416 100644
--- a/model_utils/managers.py
+++ b/model_utils/managers.py
@@ -1,7 +1,6 @@
 from __future__ import unicode_literals
 import django
 from django.db import models
-from django.contrib.gis.db import models as geomodels
 from django.db.models.fields.related import OneToOneField
 from django.db.models.query import QuerySet
 from django.core.exceptions import ObjectDoesNotExist
@@ -14,7 +13,7 @@ except ImportError: # Django < 1.5
     string_types = (basestring,)
 
 
-class InheritanceQuerySet(QuerySet):
+class InheritanceMixin(object):
     def select_subclasses(self, *subclasses):
         levels = self._get_maximum_depth()
         calculated_subclasses = self._get_subclasses_recurse(
@@ -59,17 +58,17 @@ class InheritanceQuerySet(QuerySet):
         for name in ['subclasses', '_annotated']:
             if hasattr(self, name):
                 kwargs[name] = getattr(self, name)
-        return super(InheritanceQuerySet, self)._clone(klass, setup, **kwargs)
+        return super(InheritanceMixin, self)._clone(klass, setup, **kwargs)
 
 
     def annotate(self, *args, **kwargs):
-        qset = super(InheritanceQuerySet, self).annotate(*args, **kwargs)
+        qset = super(InheritanceMixin, self).annotate(*args, **kwargs)
         qset._annotated = [a.default_alias for a in args] + list(kwargs.keys())
         return qset
 
 
     def iterator(self):
-        iter = super(InheritanceQuerySet, self).iterator()
+        iter = super(InheritanceMixin, self).iterator()
         if getattr(self, 'subclasses', False):
             # sort the subclass names longest first,
             # so with 'a' and 'a__b' it goes as deep as possible
@@ -166,14 +165,9 @@ class InheritanceQuerySet(QuerySet):
             levels = 1
         return levels
 
-
-
-class InheritanceManager(models.Manager):
+class InheritanceManagerMixin(object):
     use_for_related_fields = True
 
-    def get_queryset(self):
-        return InheritanceQuerySet(self.model)
-
     get_query_set = get_queryset
 
     def select_subclasses(self, *subclasses):
@@ -183,7 +177,15 @@ class InheritanceManager(models.Manager):
         return self.get_queryset().get_subclass(*args, **kwargs)
 
 
-class QueryManager(models.Manager):
+class InheritanceQuerySet(InheritanceMixin, QuerySet):
+    pass
+
+class InheritanceManager(InheritanceManagerMixin, models.Manager):
+    def get_queryset(self):
+        return InheritanceQuerySet(self.model)
+
+
+class QueryMixin(object):
     use_for_related_fields = True
 
     def __init__(self, *args, **kwargs):
@@ -192,7 +194,7 @@ class QueryManager(models.Manager):
         else:
             self._q = models.Q(**kwargs)
         self._order_by = None
-        super(QueryManager, self).__init__()
+        super(QueryMixin, self).__init__()
 
     def order_by(self, *args):
         self._order_by = args
@@ -200,15 +202,17 @@ class QueryManager(models.Manager):
 
     def get_queryset(self):
         try:
-            qs = super(QueryManager, self).get_queryset().filter(self._q)
+            qs = super(QueryMixin, self).get_queryset().filter(self._q)
         except AttributeError:
-            qs = super(QueryManager, self).get_query_set().filter(self._q)
+            qs = super(QueryMixin, self).get_query_set().filter(self._q)
         if self._order_by is not None:
             return qs.order_by(*self._order_by)
         return qs
 
     get_query_set = get_queryset
 
+class QueryManager(QueryMixin, models.Manager):
+    pass
 
 class PassThroughMixin(object):
     """
@@ -267,28 +271,6 @@ class PassThroughManager(PassThroughMixin, models.Manager):
     """
     pass
 
-class PassThroughGeoManager(PassThroughMixin, geomodels.GeoManager):
-    """
-    For use with GeoDjango's GeoManager to enable spatial lookups.
-    Inherit from this Manager to enable you to call any methods from your
-    custom GeoQuerySet class from your manager. Simply define your GeoQuerySet
-    class, and return an instance of it from your manager's `get_queryset`
-    method.
-
-    Alternately, if you don't need any extra methods on your manager that
-    aren't on your GeoQuerySet, then just pass your GeoQuerySet class to the
-    ``for_queryset_class`` class method.
-
-    class LocationQuerySet(GeoQuerySet):
-        def within_boundary(self):
-            return self.filter(point__within=geom)
-
-    class Location(models.Model):
-        objects = PassThroughGeoManager.for_queryset_class(LocationQuerySet)()
-
-    """
-    pass
-
 
 def create_pass_through_manager_for_queryset_class(base, queryset_cls):
     class _PassThroughManager(base):