diff --git a/src/knx/bau27B0.cpp b/src/knx/bau27B0.cpp
index c9cf495..9ed25da 100644
--- a/src/knx/bau27B0.cpp
+++ b/src/knx/bau27B0.cpp
@@ -150,4 +150,4 @@ void Bau27B0::individualAddressSerialNumberReadIndication(Priority priority, Hop
         _appLayer.IndividualAddressSerialNumberReadResponse(priority, hopType, _rfMediumObj.rfDomainAddress(), knxSerialNumber);
 }
 
-#endif // #if MEDIUM_TYPE == 2
+#endif // #ifdef USE_RF