This is a mechanical HDD drive with a 300 GB storage capacity. This model has a 2.5" form factor, which apart from this model is commonly used in SSD drives.
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Lenovo 300GB 10K SAS 2.5" 300GB SAS internal hard drive
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LENOVO 300Gb 10K
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lenovo 300gb 10k 12gbps sas 2.5in **new retail** 00wg686 - eet01