This new solid-state drive, processing technology and quality are up to the industry's high standards, it has thefollowing features: 128GB=119GB 256GB=238GB 512GB=476GB 1TB=931GB 2TB= 1862GB This is the difference in calculations between the manufacturer and your PC, sSD chip manufacturers use decimal arithmetic to calculate capacity, 1000MB= 1GB, while computer system manufacturers use binary arithmetic to calculate capacity, 1024MB = 1GB. Therefore, the actual capacity of SSD products will be different from the nominal capacity. For more information, please search "SSD actual capacity reduction" in google. 100% actual capacity, passed H2testw full disk read and write test.Please do not test with cheap adapters or cables, low quality adapters or cables will result in slower speeds. Model: Bliksem M667 SSD 2.5" SATA ⅢI 6Gb/sCapacity: 128GB, 256GB, 512GB, 1TB, 2TBChip: High-speed 3D NAND chipWeight: 44 g /1.44 oz Size: 3.94*2.75*0.28 inches (L/W/H)Interface: SATA III 6GB/S (compatible with SATA II 3GB/s).color: blackRead speed: 550 MB/S; Write speed: 480 MB/S; Operating Temperature: 32° F to 158° F (0° C to 70° C).Packaging: Packaged in a secure cardboard storage box.Compatibility: All desktop computers, laptops and other consumer electronic devices with SATA interface.Operating System: Windows 2000/7/8/8.1/10/Vista/XP/2000/ME, Linux and MacOs 10.3 and above.