КАк в OpenCart показать массу и артикул на странице с товаром?

foreach ($tags as $tag) {
$this->data['tags'][] = array(
'tag' => trim($tag),
'href' => $this->url->link('product/search', 'filter_tag=' . trim($tag))
);
}


$this->data['weight'] = round($product_info['weight']);
$this->data['art'] = $product_info['sku'];

$this->data['weight'] =
$this->weight->format($product_info['weight'], $product_info['weight_class_id']);

$this->data['weight'] = round($product_info['weight']);