Cosasco corrosion coupons are manufactured from certified materials in a wide range of metals and alloys. The surfaces of the coupons are free from scratches, tool marks, pits and other imperfections that would create measurement errors. The coupons are stamped with a unique serial number with a low stress stamp. Each coupon is packaged in an envelope treated with VCI (Vapor Corrosion Inhibitor) which prevents corrosive attack during shipment and storage.