diff --git a/lib/zin/wg/checkbtngroup/v1.php b/lib/zin/wg/checkbtngroup/v1.php
index dd7587e63b..9a6279dd76 100644
--- a/lib/zin/wg/checkbtngroup/v1.php
+++ b/lib/zin/wg/checkbtngroup/v1.php
@@ -9,9 +9,8 @@ class checkBtnGroup extends checkList
 {
     protected static array $defaultProps = array
     (
-        'inline'     => true,
-        'className'     => 'check-btn-group',
-        'type'       => 'radio'
+        'inline' => true,
+        'type'   => 'radio'
     );
 
     public static function getPageCSS(): string|false
@@ -30,4 +29,11 @@ class checkBtnGroup extends checkList
     {
         return new checkBtn(set($props));
     }
+
+    protected function build(): wg
+    {
+        $div = parent::build();
+        $div->add(setClass('check-btn-group'));
+        return $div;
+    }
 }