1 files changed, 1 insertions, 1 deletions
diff --git a/SocketHttpListener/Net/HttpListenerRequest.cs b/SocketHttpListener/Net/HttpListenerRequest.cs
index faeca78b2..667d58ea7 100644
--- a/SocketHttpListener/Net/HttpListenerRequest.cs
+++ b/SocketHttpListener/Net/HttpListenerRequest.cs
@@ -155,7 +155,7 @@ namespace SocketHttpListener.Net
                     }
                     else
                     {
-                        header = header.ToLower(CultureInfo.InvariantCulture);
+                        header = header.ToLowerInvariant();
                         _keepAlive =
                             header.IndexOf("close", StringComparison.OrdinalIgnoreCase) < 0 ||
                             header.IndexOf("keep-alive", StringComparison.OrdinalIgnoreCase) >= 0;