diff --git a/gateway/assets/index.html b/gateway/assets/index.html
index 739add10..8ac8dc48 100644
--- a/gateway/assets/index.html
+++ b/gateway/assets/index.html
@@ -158,8 +158,8 @@
                                 <md-input-container class="md-block" flex-gt-sm>
                                     <md-radio-group ng-model="invocation.contentType" layout="row" layout-align="start center">
                                         <md-radio-button value="text" class="md-primary"> Text </md-radio-button>
-                                        <md-radio-button value="json"> JSON </md-radio-button>
-                                        <md-radio-button value="binary"> Download </md-radio-button>                                        
+                                        <md-radio-button value="json" class="md-primary"> JSON </md-radio-button>
+                                        <md-radio-button value="binary" class="md-primary"> Download </md-radio-button>                                        
                                     </md-radio-group>
                                 </md-input-container>
                             </div>
diff --git a/gateway/assets/script/bootstrap.js b/gateway/assets/script/bootstrap.js
index ede2affe..fdbd74fc 100644
--- a/gateway/assets/script/bootstrap.js
+++ b/gateway/assets/script/bootstrap.js
@@ -225,7 +225,11 @@ app.controller("home", ['$scope', '$log', '$http', '$location', '$interval', '$f
                 $scope.invocationResponse = "";
                 $scope.invocationStatus = "";
                 $scope.invocationInProgress = false;
-                $scope.invocation.contentType = "text";
+                if (fn.labels && fn.labels['com.openfaas.ui.ext']) {
+                  $scope.invocation.contentType = "binary";
+                } else {
+                  $scope.invocation.contentType = "text";
+                }
                 $scope.invocation.roundTripDuration = "";
             }
         };