Quality Park 2-Side Interoffice Envelopes, Redi-Tac Box-Style, Brown Kraft, 10 x 13, 100 per Box, (63666) REDI-TAC: Unique redi-tac closure is durable and convenient VISUAL CONFIRMATION: Holes punched on both sides of the envelope allow for visual confirmation of the contents without opening MAXIMIZE: 3 Columns on each side with narrow ruling allows for maximum space for signatures DURABLE: Made from heavyweight 28 lb. brown kraft stock GREAT VALUE: Conveniently packed in 100 count to reduce the frequency of repurchasing