The housing according to the manufacturer should be equipped with the chipset "ASM1053 6G ASMedia". Windows 8.1 and Mac OS 10.9 identify the chipset but as the predecessor ASM1051. This is of course annoying, because I wanted to purchase a device with the current chipset. The function I certainly have seen no impact - Windows is the case properly as UAS device is detected, and both Windows and Mac OS, I could read and write speeds beyond the 400MB / s measure (Samsung 840 Evo with exFAT formatted) , Since the build quality looks good, I therefore forgive despite "misnomer" 4 stars and keep the housing.