100-6x6 RIGID PHOTO ~ MAILERS ENVELOPES STAY FLATS Protect important items with these rigid and durable cardboard mailers. 26 point paperboard for a rigid and clean white appearance. Perforated tab and tear system that saves you time in retrieving your item Reduces shipping costs by eliminating carton filler &amp; reducing labor. Multi-functional, expands to accept varying contents &amp; weights.