Thank you for viewing. FERNANDES ZO-3 dedicated strings, GSZ-500. Brand new, unused. These strings are specifically planned and developed for the ZO-3 scale. They cannot be used on other guitar scales. Due to long-term storage at home, there may be some string degradation. There are slight black marks on the 1st to 3rd strings, but I cannot confirm if they are rusty without opening the package. Please refrain from purchasing if you are concerned. This product will be shipped via regular mail (fixed or non-standard). Please understand that I cannot be held responsible for the delivery status or any guarantees. *Please note that regular mail does not deliver on weekends and holidays, so it may take some time. *Please refrain from negotiating the price of this product. Fernandes ZO-3 electric guitar