100 Pack - 19x24 WHITE POLY MAILERS ENVELOPES BAGS 19 x 24(USA MADE) High Quality PolyAir Self Sealing Mailers. Water, Tear and Puncture resistant. The silver inner layer provides confidentiality Pressure sensitive adhesive provides a high strength durable closure, water and dirt resistant High-efficiency mailers are perfect for shipping a wide variety of non-fragile items.