Samsung 870 EVO MZ-77E1T0B/AM 1TB is an SSD type hard drive which can fit 1 TB of data. The form factor of this SSD is 2.5".
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SAMSUNG 870 EVO 1TB 2.5 Inch SATA III Internal SSD (MZ-77E1T0B/AM)
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SAMSUNG 870 EVO SATA III SSD 1TB 2.5 Internal Solid State Hard Drive, Upgrade PC or Laptop Memory and Storage for IT Pros, Creators, ..