diff --git a/lib/Phpfastcache/Helper/Psr16Adapter.php b/lib/Phpfastcache/Helper/Psr16Adapter.php
index 0f7679bbf..e2fa5a7a0 100644
--- a/lib/Phpfastcache/Helper/Psr16Adapter.php
+++ b/lib/Phpfastcache/Helper/Psr16Adapter.php
@@ -76,7 +76,7 @@ public function get($key, $default = null)
     /**
      * @param string $key
      * @param mixed $value
-     * @param null $ttl
+     * @param null|int|\DateInterval $ttl
      * @return bool
      * @throws \Phpfastcache\Exceptions\PhpfastcacheSimpleCacheException
      */