Quickbooks Size Double Window Envelope - Inside Tint - 24# White (3 5/8 x 8 3/4) - Double Window Envelope Series (Pkg of 100) A Quantity of 100 - Quickbook Envelope - Double Window 24# White Paper - Top Wdo: 7/8 x 3 1/2, 3/8 from Left, 2 7/16 from bottom. Btm Wdo: 15/16 x 3 1/2, 7/8 from left, 11/16 from bottom. Great for mailing checks from many popular accounting programs. This envelope may be sourced from any one of a number of top brands. Ships via Priority Mail