The redesigned console is slimmer than the previous Xbox 360 model and features integrated 802.11 b/g/n Wi-Fi, TOSLINK S/PDIF optical audio output, 5 USB 2.0 ports (compared to the 3 from older versions) and a special AUX port.[12
This should be what the back of the new slim 360 looks like. The optical is to the left of the HDMI port if you are looking from the rear like this.
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