The following code displays the ordered products individual weight: $weightsql = 'select op.products_name, op.products_quantity , p.products_weight from ' . TABLE_ORDERS_PRODUCTS . ' op left join ' . TABLE_PRODUCTS . ' p on op.products_id = p.products_id where op.products_id = '.$pro['products_id']; $weightq = tep_db_query( $weightsql ); while ($weight = tep_db_fetch_array( $weightq )){ if($category_parent_id != 0)$list_items[] = $weight['products_weight'].'   '; } This shows the wieght for each of the products ordered. What I am stuck on is instead of showing seperate weights, I need to show a total weight. For example, if the product was ordered three times, and it weighs 7kg, the code at the moment is showing: Product 7.00 7.00 7.00 How would I make it show the total weight, 21kg?