diff --git a/oscar_docdata/gateway.py b/oscar_docdata/gateway.py
index bdd2f77..d0fa51e 100644
--- a/oscar_docdata/gateway.py
+++ b/oscar_docdata/gateway.py
@@ -901,6 +901,39 @@ def to_xml(self, factory):
 class Quantity(object):
     """
     An quantity for Docdata
+
+    <element name="quantity" minOccurs="1" maxOccurs="1">
+        <annotation>
+            <documentation>Quantity of this item that's being ordered.
+            </documentation>
+        </annotation>
+        <complexType>
+            <simpleContent>
+                <extension base="int">
+                    <attribute name="unitOfMeasure" use="required">
+                        <annotation>
+                            <documentation>
+                                Unit of measurement.
+
+                                The attribute can have the
+                                following values: PCS - pieces
+                                SEC- seconds BYT - bytes KB -
+                                kilobytes
+                            </documentation>
+                        </annotation>
+                        <simpleType>
+                            <restriction base="string">
+                                <enumeration value="PCS"/>
+                                <enumeration value="SEC"/>
+                                <enumeration value="BYT"/>
+                                <enumeration value="KB"/>
+                            </restriction>
+                        </simpleType>
+                    </attribute>
+                </extension>
+            </simpleContent>
+        </complexType>
+    </element>
     """
     def __init__(self, value, unit='PCS'):
         """
@@ -917,15 +950,10 @@ def __init__(self, value, unit='PCS'):
         self.unit = unit
 
     def to_xml(self, factory):
-        # Needs to be an xsd:int with an attribute
-        # Can't do that with factory.create('ns0:quantity')
-        #metadata = factory.resolver.find('ns0:quantity')
-        #ns = metadata.namespace()
-
-        element = Element('ns0:quantity')
-        element.setText(str(self.value))
-        element.set('unitOfMeasure', self.unit)
-        return element
+        node = factory.create('ns0:quantity')
+        node.unitOfMeasure = self.unit
+        node.int = self.value
+        return node
 
 
 class Invoice(object):