With CStore Essentials you can delete modifiers/qualifier quickly, these are usually items that are sold in multiple quantity at different but with the same barcode. A good example of this is your beer singles and 2 pack or your cigarettes 2 pack.
1. Go to Pricebook -> Item. Click on the Modifier button on the far right corner. Then search the item with scan code or name.
2. On the far right you will see delete button (trash bin); click on it to delete the modifier.
3. Go to Price book>Send to POS and click on “Send all items Changes”