diff --git a/config/ags/config.js b/config/ags/config.js
index 684862fc..e2597767 100644
--- a/config/ags/config.js
+++ b/config/ags/config.js
@@ -126,7 +126,7 @@ function BatteryLabel() {
     const icon = battery.bind("percent").as(p =>
         `battery-level-${Math.floor(p / 10) * 10}-symbolic`)
 
-    const percent = battery.bind("percent").as(x => x.toString) + "%"
+    const percent = battery.bind("percent").as(x => x.toString()) + "%"
 
     return Widget.Box({
         class_name: "battery",