The #10 Window Envelope (4 1/8 x 9 1/2) in 24lb. White with FDIC Security Tint is a traditional white, standard weight business envelope with an enhanced feature - it has a tinted inside pattern designed to protect sensitive information at all times. Perfect for saving time while sending letters, invoices or statements, as you can just position the address on a document to show through the envelope window instead of addressing them all individually. These highly professional envelopes are sealed by a moistenable glue located on the inside of the back flap. #10 Window Envelopes are available both plain and custom printed for company branding and creative uses, starting in small quantities of 50 to large quantities of 50,000 and more.