The original and the best archival storage product for your valuable collectables, imported from the US. Archives (formerly known as 'Snugs') are made from 4 mil thick Mylar D®, a specially produced polyester film, as opposed to plastic out of which poly-bags are produced. Mylar is universally recommended for long term storage of paper products because of the quality and chemical stability of the material. Besides its strength, it is resistant to moisture, mildew and mold and will not yellow like poly-bags with time. These bags are rigid, with a glass like finish and a rounded die cut top (unlike cheaper alternatives which are generally thinner and maybe cut square across the top). Mylites2 are a thinner 2 mil thick mylar bag, offering the same archival protection, but at a more affordable price. (note: MegaCity only stock original US Mylars from E Gerber, which are a full 4mil (100 microns) thick and feature a die-cut top, for easy loading. By comparsion, 'Collectorline' mylars, which are stocked by many of our competitors are only 75 microns thick, and feature a simply square cut top).