Can be used to install new OS or to upgrade system if machine is compatible. Power on the machine while flash drive is plugged in and immediately press and old down the Option key to bring up the one-time boot menu. Select the flash drive and follow the rest of the prompts. There may be some weird behavior from the installation if the system is connected to the internet before setup is fully complete (I.e. trying to login to your cloud account). Some Google searching can help out in situations like that or if there are other oddities. I do offer free 30 day refunds if you are not fully satisfied. Please reach out to me first through a message before opting a return case or if you have a question before purchasing.
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