You need to follow the steps below to use your Voucher Codes in ExpressTest: add your favorite products to the shopping cart, then click log in or create a new account, and then return to the ExpressTest shopping cart to select the products you need to purchase (can be a single product, multiple ExpressTest orders can also be placed together). Then jump to the payment page, select Promo Codes of your ExpressTest on the payment page, and complete the payment.