HouseLabels DYMO-Compatible 30387 3-Part Internet Postage Labels (2-5/16" x 10-1/2") -- BPA Free! (6 Rolls; 100 Labels per Roll) Label Lines International, along with Amazon Vendor Central, are the only two authorized resellers of HouseLabels products.While there are some Amazon storefronts legitimately reselling HouseLabels product, most claim to do so but do not (many times resulting in customer dissatisfaction and negative reviews for a product that we did not even produce  an unfortunate quirk in the Amazon marketplace). All HouseLabels Dymo, Brother and Avery compatible products carry the HouseLabels logo behind it. Each roll is packed in an individual mini-carton, with the HouseLabels' logo, to protect each roll from sunlight and scuffing. Each white label is blank and ready for your printing. These internet postage with delivery confirmation labels are 3-part internet postage labels. The label has a large destination and return address part, a postage part, and a special part for the electronic delivery confirmation barcode This label is required for printing concatenated barcode labels for commercial pricing from Endicia/DAZzle If you receive product that does not carry such logo, please insist on returning it to the Amazon merchant for a full refund. Rest assured that when receiving a HouseLabels product, each element of the label (the face stock, the release liner and the adhesive) has been carefully selected and thoroughly tested to ensure that you receive a quality label. 2-5/16" x 10-1/2" | Rectangle | White | Direct Thermal | BPA Free | Permanent-Adhesive | 100 Labels per Roll DYMO Printers: 300, 310, 315, 320, 330, 400, 400 Duo, 400 Twin Turbo, 450, 450 Duo, 450 Turbo, 450 Twin Turbo, 4XL, EL40, EL60, SE300, SE450 CoStar LabelWriters: XL, XL+, BC, BC+, TURBO, SE200, SE250, ACII 200 / ASCII 250