$current_tags = get_the_terms( get_the_ID(), 'product_tag' );
//only start if we have some tags
if ( $current_tags && ! is_wp_error( $current_tags ) ) {
//create a list to hold our tags
echo '<ul class="product_tags">';
//for each tag we create a list item
foreach ($current_tags as $tag) {
$tag_title = $tag->name; // tag name
$tag_link = get_term_link( $tag );// tag archive link
echo '<li><a href="'.$tag_link.'">'.$tag_title.'</a></li>';
}
echo '</ul>';
}