"Premium 3/16"" dual protection bubble for each side, 3/8"" of total bubble protection.***Note: E-lite bubble mailer is 3/16"" bubble is for each side, so the total bubble thickness is 6/16"".  We have bought samples from other sellers. Their 3/16"" bubble means the total thickness of the mailer with both size combine.***"E-lite bubble are 2 times as thick as some other China import bubble mailer."UPS, FedEx, DHL, US Postal, Canadian Postal APPROVED"Seamless bottom for maximum strength. Smooth side seams"2 sides double heat seal for extra security."Shipping labels adhere securely to the recycled Kraft paper cover