The ECUSB3S254F 2-Port Flush Mount USB 3.0 ExpressCard Adapter uses a unique form factor design that allows it to sit fully in a standard 54mm laptop ExpressCard slot without sticking out. When inserted, the USB 3.0 ports provided by the ExpressCard adapter sit flush with the sides of the laptop, creating a seamless add-on that can be left installed even while on the move, without having to worry about impact damage to either the card or the ExpressCard slot. The SuperSpeed USB 3.0 Card supports data transfer rates of up to 5Gbps, and is backward compatible with USB 2.0 (at up to 480Mbps), or USB 1.1/1.0 at up to 12/1.5 Mbps respectively - the perfect laptop accessory for users to connect USB devices, both new and old.