Ensure immediate attention! Double-window envelopes come preprinted with the statement "Important Tax Return Document Enclosed". Convenient: Self-seal saves time and makes mailing easier. Secure: Printed lining to protect your privacy. Quality: 24# white wove confidential double-window envelope Compatibility: For 1099s Miscellaneous Income and 1099-R Tax Form Envelope Size: 5 5/8 Inch x 9 Inch ~ Top Window: 1 1/8 x 3 3/8 - 1/2 from left, 3 3/4 from bottom