Abstract: A quick plug/eject concept 3.5? SATA HDD rack comprises a casing, a HDD holding set, a HDD ejecting set, a HDD vibration reduction and static electronics proof set, a Serial ATA connector (the receptacle part), and a plug-in sensor. The design of a HDD holding set and a HDD ejecting set allows user to install and uninstall a 3.5? SATA HDD by hand plug/eject movements without tool (i.e. toolless). HDD vibration reduction and static electronics proof set enhances the stability and security of the HDD by avoiding accidents caused by 3.5? HDD vibration and electrical short circuit. The Serial ATA connector provides a SATA signal connecting structure without an extra connector that might reduce the high frequency signal.