Matrox Dual/TripleHead2Go Mac
Matrox DualHead2Go and TripleHead2Go for Mac

Now Mac users can benefit from Matrox's multi-monitor expertise with the award-winning Matrox DualHead2Go and TripleHead2Go products. DualHead2Go and TripleHead2Go are palm-sized boxes that connect externally to the VGA output of the compatible Mac notebooks and Mac desktops, allowing users to attach two or three monitors to their systems, creating a multi-monitor environment. See the website for the list of compatible Macs.

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www.matrox.com/graphics/en/gxm/support/mac/home.php