Crucial kit 128GB (2x64GB) DDR5 PRO RAM 5600MHz U-DIMM CP64G56C46U5 Gaming Desktop Memory in very good, slightly used condition. Please note, the memory is compatible with the most recent generations of higher-end consumer desktop PCs and gaming systems and are U-DIMM type. However, not registered or ECC server memory, and will not work in laptops. Serial numbers are following: EB4FB9CF, EB4FBA15.