Double-window, No. 9 envelopes make mailing easy and efficient with Redi-Seal Closure. Envelopes do not require moisture to seal. Unique double-flap design keeps the gum from sticking before use. Simply raise the lower flap and press to seal. The 1-3/16 x 3-1/2 top window is positioned 3/8 from the left and 2 from the bottom. The 1 x 4 bottom window is positioned 3/8 from the left and 1/2 from the bottom. 24 lb. white wove envelopes have poly windows and inside tint for security.