10 x 13 Full Face Window Envelopes - 28lb. Bright White - Pack of 50 Size: 10 x 13 Full Face Window Envelopes / 10 in x 13 in / 10" x 13" / 254mm x 330mm Quantity: Pack of 50 Color: 28lb. Bright White USES: Catalogs, Annual Reports, Brochures, Magazines, Invitations and so much more! Applications: Business Mailings, Direct Mail, Corporate Mailings, Financial Mailings, Personal Mail. Printable on off-set printing presses and some home printers.