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The guarantee period which the company offered … their com- puters was 12 months … the date …putting them … operation and 15 months … the date … delivery. The Buyer found it rather short and wanted it to be extended … two and four months respectively. But the company agreed to extend it only … 13 and 17 months.As the Seller was responsible … the defects which were found … the equipment, they had to correct them … their expense.