diff --git a/src/components/chart/RungBuilder.vue b/src/components/chart/RungBuilder.vue
index 2c0a5f4..0331641 100644
--- a/src/components/chart/RungBuilder.vue
+++ b/src/components/chart/RungBuilder.vue
@@ -5,7 +5,7 @@
          class="d-flex flex-column align-self-start ml-2">
       <div class="flex-row align-items-center">
         <v-btn variant="outlined" style="width: 8em"
-               @click="props.builder.breakout=!props.builder.breakout">{{ name }}</v-btn>
+               @click="()=>{if (props.builder.breakout!==undefined) props.builder.breakout=!props.builder.breakout}">{{ name }}</v-btn>
         <div class="description w-100 text-center">{{description}}</div>
       </div>
       <v-text-field type="number" v-model="rungs"