Add two flushmount usb 30 ports to your expresscard enabled laptop the ecusb3s254f 2 port flush mount usb 30 expresscard adapter lets you add two usb 30 ports to your expresscard enabled laptop the usb 30 card uses a unique design that allows it to sit flush in a standard 54mm laptop expresscard slot 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 enhanced with uasp