diff --git a/ixwebsocket/IXWebSocketTransport.h b/ixwebsocket/IXWebSocketTransport.h
index 19dfafcf..96d8cae0 100644
--- a/ixwebsocket/IXWebSocketTransport.h
+++ b/ixwebsocket/IXWebSocketTransport.h
@@ -179,17 +179,6 @@ namespace ix
         std::chrono::time_point<std::chrono::steady_clock>_closingTimePoint;
         static const int kClosingMaximumWaitingDelayInMs;
 
-        // Constants for dealing with closing conneections
-        static const uint16_t kInternalErrorCode;
-        static const uint16_t kAbnormalCloseCode;
-        static const uint16_t kProtocolErrorCode;
-        static const uint16_t kNoStatusCodeErrorCode;
-        static const std::string kInternalErrorMessage;
-        static const std::string kAbnormalCloseMessage;
-        static const std::string kPingTimeoutMessage;
-        static const std::string kProtocolErrorMessage;
-        static const std::string kNoStatusCodeErrorMessage;
-
         // enable auto response to ping
         std::atomic<bool> _enablePong;
         static const bool kDefaultEnablePong;