class ConfirmPurchaseButton extends PurchaseButton
{
    /**
     * Filters the back button for Welcart normal checkout review page
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @param string $html
     * @param string $btntype
     * @return string
     */
    protected function filterBackButton($html, $btntype) {
        /**
         * Mirrored Welcart filter
         *
         * @ignore
         */
        $btnval = apply_filters('usces_filter_confirm_prebutton_value', __('Back', 'usces'));
        ob_start();
        ?>
        <form id="purchase_form" action="<?php echo USCES_CART_URL; ?>" method="post" onKeyDown="if (event.keyCode == 13) {return false;}">
            <input
                class="login-backbtn ui <?php echo $btntype; ?> button"
                name="backDelivery"
                type="submit"
                value="<?php echo esc_attr($btnval); ?>"
            />
        </form>
        <?php
        $html = ob_get_clean();

        return $html;
    }
}