/*
 *  Custom tab for shop page
 */
add_filter('woocommerce_product_tabs', 'wpb_new_product_tab');

function wpb_new_product_tab($tabs) {
    // Add the new tab Specification
    $tabs['specifications'] = array(
        'title' => __('Specifications', 'text-domain'),
        'priority' => 20,
        'callback' => 'wpb_new_product_tab_content' // callback function
    );
    $tabs['delivery'] = array(
        'title' => __('Delivery', 'text-domain'),
        'priority' => 40,
        'callback' => 'wpb_delivery_tab_content' //callback function
    );
    return $tabs;
}
//Callback Function For Specification Tab
function wpb_new_product_tab_content() {
    // The new tab content
    echo '<div class="list-mark list-mark_small">';
    if (get_field('specifications')) {
        the_field('specifications', get_the_ID());
    }
    echo '</div>';
}

//Callback Function For delivery Tab
function wpb_delivery_tab_content() {
    // The new tab content
    echo '<div class="list-mark list-mark_small">';
    if (get_field('delivery')) {
        the_field('delivery', get_the_ID());
    }
    echo '</div>';
}