diff --git a/postinstall_runner_action.h b/postinstall_runner_action.h
index 0136ee2..fea0a39 100644
--- a/postinstall_runner_action.h
+++ b/postinstall_runner_action.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef CHROMEOS_PLATFORM_UPDATE_ENGINE_POSTINSTALL_RUNNER_ACTION_H__
-#define CHROMEOS_PLATFORM_UPDATE_ENGINE_POSTINSTALL_RUNNER_ACTION_H__
+#ifndef CHROMEOS_PLATFORM_UPDATE_ENGINE_POSTINSTALL_RUNNER_ACTION_H_
+#define CHROMEOS_PLATFORM_UPDATE_ENGINE_POSTINSTALL_RUNNER_ACTION_H_
 
 #include <string>
 
@@ -60,4 +60,4 @@
 
 }  // namespace chromeos_update_engine
 
-#endif  // CHROMEOS_PLATFORM_UPDATE_ENGINE_POSTINSTALL_RUNNER_ACTION_H__
+#endif  // CHROMEOS_PLATFORM_UPDATE_ENGINE_POSTINSTALL_RUNNER_ACTION_H_