300 Pcs 7.5" x 10.5" White 2 Mil Poly Mailer Envelopes Shipping Bags with Self Adhesive, Waterproof and Tear-proof Postal Bags Adhesive: Synthetic rubber  Hotmelt,  minimum +/- 1/8. Lip Size: 1.5 +/-  & Paper Liner: Clear with antistat. Opacity: Business card inside the mailer should not be visible under UV light. White/Grey Exterior, Black Interior (Interior color of mailer is subject to change). 2-millimeter thickness (+/- 5%) & it is used to Ship Lighter Weight items.