00UP735 512GB is an SSD type hard drive which can fit 512 GB of data. The form factor is M.2, which allows the hard drive to connect directly to the motherboard.
From SmartTeck
Lenovo SSD M.2 2280 PCIe NVMe 512GB OPAL 2 0 FRU SSD M.2 2280 PCIe NVM -
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lenovo 512 gb ssd m.2 2280 pcie3x4 00up735 - eet01
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LENOVO 512 Gb Ssd M.2