There's an optional VESA mount adapter available for the Apple Cinema Display (20-inch DVI), Apple Cinema HD Display (23-inch DVI), and Apple Cinema HD Display (30-inch DVI).
The VESA mount adapter allows compatible displays to be used with a variety of alternate mounting solutions, such as wall mounts and zero-footprint articulating arms based on the VESA flat panel mounting interface (FPMI). Instructions and a hex tool for removing the desktop stand provided with the display are provided with the adapter. You can also get the installation instructions here.
The Apple flat-panel display with the VESA mount adapter uses a 100 mm mounting surface and, when attached, complies with the VESA MIS-D, 100, C version of the specification.
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