#9 Double Window Security Business Mailing Envelopes for Invoices, Statements and Legal Documents – GUMMED Closure, Security Tinted – Size 3-7/8 x 8-7/8 – White – 24 LB – Case / 2500 Ct. (30129-2500)DOUBLE WINDOW SECURITY ENVELOPES; tired of cheap paper envelopes that can be easily seen through? Our Double Window Security Envelopes are ultra-secure and perfect for mailing invoices, statements and legal documents, with secure moisture activated gummed seal and tinted security wave patternsTINTED SECURITY WAVE PATTERN; perfect for mailing invoices, statements, standard business, legal documents and sensitive correspondence, our #9 Envelopes are printed with a secure tinted wave pattern, easily obscuring numbers and data for premium, added security compared to other cheap envelopesDUAL WINDOW DESIGN; easily read dual windows for everyday business mailings to easily display postal addresses. Each envelope contains two front windows, a 1-3/16″ X 3-1/2″ top window positioned 3/8″ from the left and 2″ from the bottom and the bottom 1 X 4″ window is 3/8″ from the left and 1/2″ from the bottomLONG LASTING SUPPLY; perfect for everyday business use, our envelopes are provided as an ultra-long lasting, with a case of 5 packs, each pack of these containing 500 envelope supply measuring 3-7/8 x 8-7/8, with a total of 2,500 envelopes, ideal for mass mailing of business documents!