diff --git a/x-pack/plugins/triggers_actions_ui/public/common/expression_items/of.scss b/x-pack/plugins/triggers_actions_ui/public/common/expression_items/of.scss
index 2cb799808af0d..6b55a43201d16 100644
--- a/x-pack/plugins/triggers_actions_ui/public/common/expression_items/of.scss
+++ b/x-pack/plugins/triggers_actions_ui/public/common/expression_items/of.scss
@@ -1,3 +1,3 @@
 .actOf__aggFieldContainer {
-  width: $euiSize * 30;
+  width: $euiSize * 29;
 }