Quality Park Double Window #9 Invoice Envelope, Security Tint, 3.875 Inches x 8.875 Inches, White, Box of 100 (24525) White window envelope features a gummed closure. Envelope is security tinted and includes a bottom left window (3 1/2w x 1 1/4h) plus a top left window (4w x 1h) Double window shows mailing and return address White wove finish with a gummed closure Blue security tint