diff --git a/src/Annotation/MQTTSubscribe.php b/src/Annotation/MQTTSubscribe.php
index fd69f76..9a5928d 100644
--- a/src/Annotation/MQTTSubscribe.php
+++ b/src/Annotation/MQTTSubscribe.php
@@ -20,5 +20,5 @@ class MQTTSubscribe extends MQTTEvent
     /**
      * @var int
      */
-    public $type = Types::SUBSCRIBE;
+    public int $type = Types::SUBSCRIBE;
 }