diff --git a/HttpServer/Http/Response.php b/HttpServer/Http/Response.php
index 6ad2a412..bd14444d 100644
--- a/HttpServer/Http/Response.php
+++ b/HttpServer/Http/Response.php
@@ -48,7 +48,7 @@ class Response extends Application
 		self::HTML => HtmlFormatter::class
 	];
 
-	public $fd = 0;
+	public int $fd = 0;
 
 	/**
 	 * @param $format