diff --git a/modules/sale_stock_quantity/sale.py b/modules/sale_stock_quantity/sale.py
index f972934695..7f55756d0a 100644
--- a/modules/sale_stock_quantity/sale.py
+++ b/modules/sale_stock_quantity/sale.py
@@ -9,21 +9,12 @@ from operator import attrgetter
 from trytond.i18n import gettext
 from trytond.model import ModelView, Workflow, fields
 from trytond.pool import Pool, PoolMeta
-from trytond.tools import grouped_slice
+from trytond.tools import grouped_slice, sortable_values
 from trytond.transaction import Transaction
 
 from .exceptions import StockQuantityError, StockQuantityWarning
 
 
-def sortable_values(func):
-    def wrapper(*args, **kwargs):
-        result = list(func(*args, **kwargs))
-        for i, value in enumerate(list(result)):
-            result[i] = (value is None, value)
-        return result
-    return wrapper
-
-
 class Sale(metaclass=PoolMeta):
     __name__ = 'sale.sale'
 
diff --git a/trytond/CHANGELOG b/trytond/CHANGELOG
index 57989fd0e7..e0ed15b4c6 100644
--- a/trytond/CHANGELOG
+++ b/trytond/CHANGELOG
@@ -1,3 +1,4 @@
+* Support list of single value in sortable_values tools
 * Allow resetting password of user via RPC
 * Support cached_property on object with __slots__
 * Allow creating indexes concurrently
diff --git a/trytond/doc/ref/tools/misc.rst b/trytond/doc/ref/tools/misc.rst
index 4b0caad5a5..fa531aec8b 100644
--- a/trytond/doc/ref/tools/misc.rst
+++ b/trytond/doc/ref/tools/misc.rst
@@ -56,6 +56,10 @@ Miscellaneous
 
    Convert the string for full text if it does not contain any wild cards.
 
+.. function:: sortable_values(func)
+
+   Decorator that makes returned list of values sortable.
+
 .. function:: sql_pairing(x, y)
 
    Return an SQL expression that pairs SQL integers x and y.
diff --git a/trytond/trytond/tests/test_tools.py b/trytond/trytond/tests/test_tools.py
index e26145ed7f..c2ae439f52 100644
--- a/trytond/trytond/tests/test_tools.py
+++ b/trytond/trytond/tests/test_tools.py
@@ -283,7 +283,7 @@ class ToolsTestCase(unittest.TestCase):
         "Test hyphenate in slugify"
         self.assertEqual(slugify('foo bar', hyphenate='_'), 'foo_bar')
 
-    def test_sortable_values(self):
+    def test_sortable_values_couple(self):
         def key(values):
             return values
 
@@ -302,6 +302,25 @@ class ToolsTestCase(unittest.TestCase):
                 (('a', 1), ('b', None)),
                 ])
 
+    def test_sortable_values_single(self):
+        def key(values):
+            return values
+
+        values = [
+            (1, None),
+            (1, 3),
+            (1, 2),
+            ]
+
+        with self.assertRaises(TypeError):
+            sorted(values, key=key)
+        self.assertEqual(
+            sorted(values, key=sortable_values(key)), [
+                (1, 2),
+                (1, 3),
+                (1, None),
+                ])
+
     def test_firstline(self):
         "Test firstline"
         for text, result in [
diff --git a/trytond/trytond/tools/misc.py b/trytond/trytond/tools/misc.py
index 0529ff88c8..c0fb5cab49 100644
--- a/trytond/trytond/tools/misc.py
+++ b/trytond/trytond/tools/misc.py
@@ -12,9 +12,9 @@ import types
 import unicodedata
 import warnings
 from array import array
-from collections.abc import Sized
+from collections.abc import Iterable, Sized
 from functools import wraps
-from itertools import islice, tee, zip_longest
+from itertools import chain, islice, tee, zip_longest
 
 from sql import Literal
 from sql.conditionals import Case
@@ -286,12 +286,14 @@ def slugify(value, hyphenate='-'):
 
 
 def sortable_values(func):
-    "Decorator that makes list of couple values sortable"
+    "Decorator that makes list of values sortable"
     @wraps(func)
     def wrapper(*args, **kwargs):
         result = list(func(*args, **kwargs))
-        for i, (name, value) in enumerate(list(result)):
-            result[i] = (name, value is None, value)
+        for i, value in enumerate(list(result)):
+            if not isinstance(value, Iterable):
+                value = [value]
+            result[i] = tuple(chain((k is None, k) for k in value))
         return result
     return wrapper