diff --git a/src/Elasticsearch/Endpoints/Cat/ThreadPool.php b/src/Elasticsearch/Endpoints/Cat/ThreadPool.php
index 08f3aa5c5..4128c60e0 100644
--- a/src/Elasticsearch/Endpoints/Cat/ThreadPool.php
+++ b/src/Elasticsearch/Endpoints/Cat/ThreadPool.php
@@ -38,6 +38,7 @@ protected function getParamWhitelist()
             'help',
             'v',
             'full_id',
+            'size'
         );
     }
 
diff --git a/src/Elasticsearch/Namespaces/CatNamespace.php b/src/Elasticsearch/Namespaces/CatNamespace.php
index 2a0732727..543ef5bce 100644
--- a/src/Elasticsearch/Namespaces/CatNamespace.php
+++ b/src/Elasticsearch/Namespaces/CatNamespace.php
@@ -381,6 +381,7 @@ public function snapshots($params = array())
      *        ['help']           = (bool) Return help information
      *        ['v']              = (bool) Verbose mode. Display column headers
      *        ['full_id']        = (bool) Enables displaying the complete node ids
+     *        ['size']           = (enum) The multiplier in which to display values ([ "", "k", "m", "g", "t", "p" ])
      *
      * @param $params array Associative array of parameters
      *