Your satisfaction with our products is what matters MOST to us at SIN-MIN! If you're not happy with your unused/unopened SIN-MIN product, you can return* it to us for a full refund of the product cost. We cannot refund opened and/or used products. Because we offer free shipping on all US orders, the cost of postage for the return is to be covered by the customer and will not be included in the refund amount of the product cost. We recommend using USPS for returns under 3 lbs.