Shipping will be calculated on the certificate as the masks will be mailed to the person(s) you are purchasing the G.C.'s for. Should you wish to purchase several sets for the person you are purchasing a Gift Certificate for, simply choose the number of multiples in the item field that you wish to purchase. Upon completion of your order, a pdf Gift Certificate for the amount chosen will be emailed to you and will include a "coupon code" for the beneficiary to input when they make their choice(s) and complete the check out of their card. The value of the GC will be deducted from their purchase. Thank you for caring and sharing.