diff --git a/classes/commerce_amazon_mws.Mapping.php b/classes/commerce_amazon_mws.Mapping.php
index 70d0ed2..64b9926 100644
--- a/classes/commerce_amazon_mws.Mapping.php
+++ b/classes/commerce_amazon_mws.Mapping.php
@@ -91,6 +91,9 @@ class CommerceAmazonMWSTypeMapping {
               // Avoid empty tags or NULL values.
               $value = $this->transposeVariation($variation, $amazon_field_key, $drupal_field_key);
               if (!is_null($value)) {
+                // Last and final call to alter the value.
+                drupal_alter('amazon_mws_variation_value', $value, $amazon_field_key, $drupal_field_key, $variation);
+
                 $data[$idx][$amazon_field_key] = $value;
               }
             }
@@ -115,6 +118,9 @@ class CommerceAmazonMWSTypeMapping {
           // avoid empty tags or NULL values.
           $value = $this->transposeVariation($this->node, $amazon_field_key, $drupal_field_key);
           if (!is_null($value)) {
+            // Last and final call to alter the value.
+            drupal_alter('amazon_mws_variation_value', $value, $amazon_field_key, $drupal_field_key, $variation);
+
             $data[$amazon_field_key] = $value;
           }
         }
diff --git a/includes/commerce_amazon_mws.api.php b/includes/commerce_amazon_mws.api.php
new file mode 100644
index 0000000..56be1f0
--- /dev/null
+++ b/includes/commerce_amazon_mws.api.php
@@ -0,0 +1,25 @@
+<?php
+
+/**
+ * @file
+ * Hooks related to commerce_amazon_mws module.
+ */
+
+/**
+ * Allows altering the product variation field value before it is transposed.
+ *
+ * @param array $data
+ *   The field value.
+ * @param string $amazon_field_key
+ *   The amazon field key name.
+ * @param string $drupal_field_key
+ *   The Drupal field key name.
+ * @param object $product
+ *   The product entity.
+ */
+function hook_amazon_mws_variation_value_alter(&$data, $amazon_field_key, $drupal_field_key, $product) {
+  // Let's send back the correct stock quantity for this amazon feed.
+  if ($amazon_field_key == 'SKU') {
+    // Do something.
+  }
+}