Aegis Padlock Fortress 512GB USB 3.0 is an SSD type hard drive which can fit 512 GB of data. The form factor is 2.5" which is standard for SSD drives.
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Apricorn Aegis Fortress SSD USB 3.0 512GB Black A25-3PL256-S512F
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Apricorn Aegis Fortress SSD USB 3.0 512GB Black A25-3PL256-S512F