Standard 5.25 -inch CD-ROM optical drive bay dimension, fits most ATX/MATX desktop computer cases; 4 mixed ports: USB-C + USB 3.0 Type-A to connect storage, phones, mouse, keyboard and other peripherals; Comes with integrated 20Pin internal cable for direct, stable connection to motherboard USB 3.0 header; Front-mounted ports for easy plug/unplug, no need to bend down to access rear case interfaces; 5Gbps high-speed USB 3.0 transmission, driver-free plug-and-play for Windows & macOS