The dimensions on the list are the outer dimensions of the envelope padded bag. External Dimensions Inner Dimensions 4.2"x5" 3.5"x5" 5"x7" 4.5"x7" 5.8"x7.8" 5"x7.8" 7"x9" 6.4"x9" 9.8"x11.7" 9"x11.7" 11"x14.5" 10.2"x14.5" 13"x15.8" 12.2"x15.8" 15"x18.2" 14"x18" 19.7"x23.7" 19.5"x22.5" Material: Polyethylene Self Sealing (Just peel-n-seal)– keeps contents secure and tamper -evident and easy to use. Extra Tough Bubble Inside Easy to use – Prepare shipments quickly; these mailers are perfect for shipping a wide variety of items. High-slip bubble cushioning allows for easy product insertion and removal. Shipping labels adhere securely to the surface Lightweight – Air bubble cushioning along with the polythelene exterior material provide exceptionally light protection. Lower shipping costs combined with faster shipment preparation equals big savings Confidential – Completely opaque for content privacy and professional appearance Carrier approved – Use for all of your shipments with all carriers including Canada Post, UPS, FedEx, DHL, USPS and more Environmentally friendly – These mailers are 100% recyclable Self sealing; water and tear resistant.