500#10 Double Window Flip & Seal White Security Envelopes - 9" 3/8 X 4" 1/8 10 Double Window White Security Envelope Flip & Seal Fold flap and press for a quick secure seal water required Designed to fit Invoices & Statements Dimensions 9 3 by 8 inches by 4 1by 8 inches 24 Pound Double Window