4x8 poly bubble mailers are excellent for shipping secure items! I personally use these for raw card shipments and putting Pokemon slabs inside. Third picture shows you can’t see through it The product is a set of 100 white poly mailer bubble mailers with a 4cm sealing flap. Made of 4-layer composite polyethylene bubble film, these padded envelopes are water-proof, moisture-resistant, and tear-resistant. They are approved by USPS, UPS, DHL, and FedEx for shipping. The self-sealing feature ensures secure delivery of your items while providing protection against shock and vibration during transit.
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