diff --git a/tailbone/diffs.py b/tailbone/diffs.py
index 8303d9e9..98253c57 100644
--- a/tailbone/diffs.py
+++ b/tailbone/diffs.py
@@ -2,7 +2,7 @@
 ################################################################################
 #
 #  Rattail -- Retail Software Framework
-#  Copyright © 2010-2024 Lance Edgar
+#  Copyright © 2010-2023 Lance Edgar
 #
 #  This file is part of Rattail.
 #
@@ -27,8 +27,6 @@ Tools for displaying data diffs
 import sqlalchemy as sa
 import sqlalchemy_continuum as continuum
 
-from rattail.enum import CONTINUUM_OPERATION
-
 from pyramid.renderers import render
 from webhelpers2.html import HTML
 
@@ -275,8 +273,6 @@ class VersionDiff(Diff):
         return {
             'key': id(self.version),
             'model_title': self.title,
-            'operation': CONTINUUM_OPERATION.get(self.version.operation_type,
-                                                 self.version.operation_type),
             'diff_class': self.nature,
             'fields': self.fields,
             'values': values,
diff --git a/tailbone/menus.py b/tailbone/menus.py
index 09d6f3f0..3ddee095 100644
--- a/tailbone/menus.py
+++ b/tailbone/menus.py
@@ -394,11 +394,6 @@ class TailboneMenuHandler(WuttaMenuHandler):
                     'route': 'products',
                     'perm': 'products.list',
                 },
-                {
-                    'title': "Product Costs",
-                    'route': 'product_costs',
-                    'perm': 'product_costs.list',
-                },
                 {
                     'title': "Departments",
                     'route': 'departments',
@@ -456,11 +451,6 @@ class TailboneMenuHandler(WuttaMenuHandler):
                     'route': 'vendors',
                     'perm': 'vendors.list',
                 },
-                {
-                    'title': "Product Costs",
-                    'route': 'product_costs',
-                    'perm': 'product_costs.list',
-                },
                 {'type': 'sep'},
                 {
                     'title': "Ordering",
diff --git a/tailbone/templates/master/view.mako b/tailbone/templates/master/view.mako
index 118c028c..0a1f9c62 100644
--- a/tailbone/templates/master/view.mako
+++ b/tailbone/templates/master/view.mako
@@ -196,7 +196,6 @@
 
                   <p class="block has-text-weight-bold">
                     {{ version.model_title }}
-                    ({{ version.operation }})
                   </p>
 
                   <table class="diff monospace is-size-7"
diff --git a/tailbone/views/master.py b/tailbone/views/master.py
index 21a5e58f..2e7ac147 100644
--- a/tailbone/views/master.py
+++ b/tailbone/views/master.py
@@ -903,7 +903,7 @@ class MasterView(View):
 
     def valid_employee_uuid(self, node, value):
         if value:
-            model = self.app.model
+            model = self.model
             employee = self.Session.get(model.Employee, value)
             if not employee:
                 node.raise_invalid("Employee not found")
@@ -939,7 +939,7 @@ class MasterView(View):
 
     def valid_vendor_uuid(self, node, value):
         if value:
-            model = self.app.model
+            model = self.model
             vendor = self.Session.get(model.Vendor, value)
             if not vendor:
                 node.raise_invalid("Vendor not found")
@@ -1382,7 +1382,7 @@ class MasterView(View):
         return classes
 
     def make_revisions_grid(self, obj, empty_data=False):
-        model = self.app.model
+        model = self.model
         route_prefix = self.get_route_prefix()
         row_url = lambda txn, i: self.request.route_url(f'{route_prefix}.version',
                                                         uuid=obj.uuid,
@@ -2153,7 +2153,7 @@ class MasterView(View):
         Thread target for executing an object.
         """
         app = self.get_rattail_app()
-        model = self.app.model
+        model = self.model
         session = app.make_session()
         obj = self.get_instance_for_key(key, session)
         user = session.get(model.User, user_uuid)
@@ -2594,7 +2594,7 @@ class MasterView(View):
         """
         # nb. self.Session may differ, so use tailbone.db.Session
         session = Session()
-        model = self.app.model
+        model = self.model
         route_prefix = self.get_route_prefix()
 
         info = session.query(model.TailbonePageHelp)\
@@ -2617,7 +2617,7 @@ class MasterView(View):
         """
         # nb. self.Session may differ, so use tailbone.db.Session
         session = Session()
-        model = self.app.model
+        model = self.model
         route_prefix = self.get_route_prefix()
 
         info = session.query(model.TailbonePageHelp)\
@@ -2639,7 +2639,7 @@ class MasterView(View):
 
         # nb. self.Session may differ, so use tailbone.db.Session
         session = Session()
-        model = self.app.model
+        model = self.model
         route_prefix = self.get_route_prefix()
         schema = colander.Schema()
 
@@ -2673,7 +2673,7 @@ class MasterView(View):
 
         # nb. self.Session may differ, so use tailbone.db.Session
         session = Session()
-        model = self.app.model
+        model = self.model
         route_prefix = self.get_route_prefix()
         schema = colander.Schema()
 
@@ -5541,7 +5541,7 @@ class MasterView(View):
                                   input_file_templates=True,
                                   output_file_templates=True):
         app = self.get_rattail_app()
-        model = self.app.model
+        model = self.model
         names = []
 
         if simple_settings is None:
@@ -6100,7 +6100,7 @@ class MasterView(View):
                         renderer='json')
 
 
-class ViewSupplement:
+class ViewSupplement(object):
     """
     Base class for view "supplements" - which are sort of like plugins
     which can "supplement" certain aspects of the view.
@@ -6127,7 +6127,6 @@ class ViewSupplement:
     def __init__(self, master):
         self.master = master
         self.request = master.request
-        self.app = master.app
         self.model = master.model
         self.rattail_config = master.rattail_config
         self.Session = master.Session
@@ -6161,7 +6160,7 @@ class ViewSupplement:
         This is accomplished by subjecting the current base query to a
         join, e.g. something like::
 
-           model = self.app.model
+           model = self.model
            query = query.outerjoin(model.MyExtension)
            return query
         """
diff --git a/tailbone/views/products.py b/tailbone/views/products.py
index ae6c550c..c546a0f4 100644
--- a/tailbone/views/products.py
+++ b/tailbone/views/products.py
@@ -34,7 +34,7 @@ import sqlalchemy_continuum as continuum
 
 from rattail import enum, pod, sil
 from rattail.db import api, auth, Session as RattailSession
-from rattail.db.model import Product, PendingProduct, ProductCost, CustomerOrderItem
+from rattail.db.model import Product, PendingProduct, CustomerOrderItem
 from rattail.gpc import GPC
 from rattail.threads import Thread
 from rattail.exceptions import LabelPrintingError
@@ -2668,78 +2668,6 @@ class PendingProductView(MasterView):
                         permission=f'{permission_prefix}.ignore_product')
 
 
-class ProductCostView(MasterView):
-    """
-    Master view for Product Costs
-    """
-    model_class = ProductCost
-    route_prefix = 'product_costs'
-    url_prefix = '/products/costs'
-    has_versions = True
-
-    grid_columns = [
-        '_product_key_',
-        'vendor',
-        'preference',
-        'code',
-        'case_size',
-        'case_cost',
-        'pack_size',
-        'pack_cost',
-        'unit_cost',
-    ]
-
-    def query(self, session):
-        """ """
-        query = super().query(session)
-        model = self.app.model
-
-        # always join on Product
-        return query.join(model.Product)
-
-    def configure_grid(self, g):
-        """ """
-        super().configure_grid(g)
-        model = self.app.model
-
-        # product key
-        field = self.get_product_key_field()
-        g.set_renderer(field, self.render_product_key)
-        g.set_sorter(field, getattr(model.Product, field))
-        g.set_sort_defaults(field)
-        g.set_filter(field, getattr(model.Product, field))
-
-        # vendor
-        g.set_joiner('vendor', lambda q: q.join(model.Vendor))
-        g.set_sorter('vendor', model.Vendor.name)
-        g.set_filter('vendor', model.Vendor.name, label="Vendor Name")
-
-    def render_product_key(self, cost, field):
-        """ """
-        handler = self.app.get_products_handler()
-        return handler.render_product_key(cost.product)
-
-    def configure_form(self, f):
-        """ """
-        super().configure_form(f)
-
-        # product
-        f.set_renderer('product', self.render_product)
-        if 'product_uuid' in f and 'product' in f:
-            f.remove('product')
-            f.replace('product_uuid', 'product')
-
-        # vendor
-        f.set_renderer('vendor', self.render_vendor)
-        if 'vendor_uuid' in f and 'vendor' in f:
-            f.remove('vendor')
-            f.replace('vendor_uuid', 'vendor')
-
-        # futures
-        # TODO: should eventually show a subgrid here?
-        f.remove('futures')
-
-
 def defaults(config, **kwargs):
     base = globals()
 
@@ -2749,9 +2677,6 @@ def defaults(config, **kwargs):
     PendingProductView = kwargs.get('PendingProductView', base['PendingProductView'])
     PendingProductView.defaults(config)
 
-    ProductCostView = kwargs.get('ProductCostView', base['ProductCostView'])
-    ProductCostView.defaults(config)
-
 
 def includeme(config):
     defaults(config)