diff --git a/app/Models/ProductCharacteristicsMaster.php b/app/Models/ProductCharacteristicsMaster.php
index 931c04c..124040b 100644
--- a/app/Models/ProductCharacteristicsMaster.php
+++ b/app/Models/ProductCharacteristicsMaster.php
@@ -18,6 +18,7 @@ class ProductCharacteristicsMaster extends Model
         'machine_id',
         'characteristics_type',
         'name',
+        'category',
         'inspection_type',
         'lower',
         'upper',