The Best Solution for Easier Access on Your iMac: Add Four USB 3.0 Ports to The Front Side. Supports Transfer Speeds up to 5Gbps (USB 3.0), 480Mbps (USB 2.0), 12Mbps (USB 1.1Exclusively Designed for the iMac Slim Uni-Body Model, Released November, 2012 or Later. (21 inch / 27 inch / 5K) Backwards Compatible, USB 2.0 and USB 1.1. Easy Setup, Plug & Play, Hot-Swappable