Top loading Stayflats® Plus Mailers open at the narrower side. • Peel and seal closure keeps contents secure during shipment. • Mailers feature a pull tab strip for easy opening. • Rigid construction - no additional stiffeners needed. • Made from 100% Recycled paperboard (.028 kraft chipboard). • Over 97% post-consumer content. • The First Dimension for each mailer listed below is the size of the opening.