Guming group purchase of double cups is a coupon form, which can be used once. Double cup means buy one get one free, that is, you can get another drink for free when you buy one drink. The way to use double cups is very simple, just show the coupons to the staff at the cashier of Gumingmen Store for scanning. When using coupons, you need to pay attention to some details, such as the duration and scope of use. Coupons will not be used if they exceed the use period or are not within the range specified by Gumingmen Store. In addition, the rules for each ancient tea group to buy double cups may be slightly different. Please read the instructions on the coupons carefully.