diff --git a/Message/Http/Header.php b/Message/Http/Header.php
index 3e1a40581..be5ac458c 100644
--- a/Message/Http/Header.php
+++ b/Message/Http/Header.php
@@ -90,6 +90,14 @@ class Header extends HeaderAbstract
 
         return true;
     }
+    
+    /**
+     * {@inheritdoc}
+     */
+    public function getProtocolVersion() : string
+    {
+        return $_SERVER['SERVER_PROTOCOL'] ?? 'HTTP/1.1';
+    }
 
     /**
      * Is security header.