Check the listing for details. 50 Poly 19x24 White Poly Mailers Shipping Envelopes Mailing Bags 2.5 Mil. Color: White/Grey, Condition: New. Listed at 19.99 USD. poly mailers: Size: 19"x24" Thickness: 2.5 Millimeter Adhesive: Synthetic rubber – Hot melt, ½” minimum +/- 1/4”. Opacity: Business card inside the mailer should not be visible under UV light. Labels adhere easily, Lightweight saves on postage. Puncture resistant and tamper/water proof. USPS,UPS,Fedex,DHL Approved. Fast Shipping! Model #8 Color White/Grey MPN Does Not Apply Brand Reliable Mailers Sizes 19x24 Exterior Size 19'' x 24'' Thickness 2.5 mil UPC Does not apply .