Poly mailer bags interior dimensions 24 x 24 is high slip and space-efficient to save on postage fees Mailing envelopes exterior dimensions 24 x 24.5 has durable hot-seal seams and a self-adhesive closure Pack of 500 wholesale mailers created out of high strength polyethylene material Top-quality opaque mailing bags conceal contents while leaving a lasting impression Polybags are perfect for shipping non-fragile products like apparel medication or periodicals