100 Pink Mailing Bags 305mm x 405mm + Lip, 100% Opaque-100% Recyclable Our mailing bags are manufactured in a 3 layer extruded film. This film gives the bags strength and most importantly, makes the bag very opaque and non see through. Our bags are made thicker than our competitors, The thickness of the film is 50mu or 200gauge, weight is Approx 11 gramms per bag +/- All of our Plastic postage bags are made from Strong Polythene LDPE and are 55 Micron thicknes, made from opaque Plastic in various colours. They have a permanent Peel and seal closure with high tear resistance. How to find the correct bag for the items you are despatching, firstly lay out your item and measure the long and short dimensions of it, and then check the sizes quoted in the Heading above are close to the size you need , The sizes quoted don’t include the flap.