FREE MAILBOX Receive an additional 3 Months Free with min. 12 Month Mailbox Service Agreement. Valid on New Box Rental only. Limit one coupon per customer. This offer not good in combination with any other offers. Valid at participating locations. Restrictions apply.2017 United Parcel Service of America, Inc.Exp. 5/7/21. Go to LocalFlavor.com for more coupons.