3812440 256GB is an SSD type hard drive which can fit 256 GB of data. The form factor is 2.5" which is common for SSD drives.
From Amazon
Intenso 2.5 Inch SSD SATA III Top Performance 256 GB
Conrad Electronic
Intenso Top Performance 256 GB 2.5 (6.35 cm) internal SSD SATA 6 Gbps Retail 3812440
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