diff --git a/src/API/Node.php b/src/API/Node.php
index c12b9e2..20643e9 100644
--- a/src/API/Node.php
+++ b/src/API/Node.php
@@ -53,11 +53,11 @@ public function configuration(): array
     /**
      * Get the node fee statistics.
      *
-     * @param integer|null $days
-     * 
+     * @param int|null $days
+     *
      * @return array
      */
-    public function fees(integer $days = null): array
+    public function fees(int $days = null): array
     {
         return $this->get('node/fees', ['query' => ['days' => $days]]);
     }